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tonight on "20/20" -- sneaking suspicions. >> i cannot believe this. this man has killed my momma. >> this man, an innocent husband or a cynical murderer who did in their rich relatives? >> what happened to your sister when the money ran out? >> what happened to her? she died. >> does this family see something suspicious in this convicted felon, with a trail of angry ex-wives? wife number three. >> i felt like i was being pois poisoned. >> wife number four. >> i'll be honest with you. if something happened to me, he needs to be investigated. >> and wife number one, choking on a throat lozenge? or is it is their greed talking after a tragic accident? tonight, we follow the clues. her hidden journal. >> nothing but takes, takes,

takes. >> police recordings, and a new wife to be entering the picture. wife number six, just months after wife number five was laid to rest. >> you have to know whether or not you murdered shirley. >> no, i did not. >> what a grieving family does, when there's nothing to go on, except sneaking suspicions. here now, elizabeth vargas and david muir. >> good evening. highly suspicious or just highly tragic? those are the conflicts sides of the coin tonight. a woman found dead in her bedroom. was it an accident? her family wants to know, because they have the sneaking suspicions. >> her autopsy includes four key words. manner of death, undetermined. so, remember, as you watch, no charges, no arrest, just what he says versus what they say. but after the possible clues jim avila has sorted through, what would you say? >> reporter: down around mobile, alabama, near the gulf of

mexico, a short drive takes you through loxley, once a sleepy lumber town, today famous for absolutely nothing. but now, on a street called camelot in a house that here passes for a castle, there is no bright shining moment, just a dark mystery of sudden unexplained death. >> this interview is with michael allen wool sleger. this is in reference to the wife. >> reporter: the wife who died suddenly, but who was not murdered. >> do you remember her falling? >> reporter: or if she was? >> as she falls back, she's gonna strike the floor pretty hard. >> reporter: what do you really think happened, chester? >> man, i hate to say this; i think someone murdered my sister. >> reporter: shirley seitz fell for doctor mike wohlschlaeger. fell hard, and fell fast. "how do you do," to "i do," in three months flat. but shirley wasn't his first

bride or his second or his third or even his fourth. shirley was number five. some with tales to tell about their marriage to mike and more importantly how their marriages ended. to be fair, this was wedding number five for shirley, too. and up in northern alabama, shirley's family, the thomases, wanted to be happy for her. buff they could not. >> i didn't like him at all. i just have to admit that. >> me being a minister, i said to her, "are you sure?" >> reporter: shirley's daughter, sharon, was ready to throw something, and it wasn't rice. >> please don't do this, mama. don't do this, please, mama, don't do this. >> reporter: whatever their worries about her latest trip to the altar, shirley's family is more than proud of her higher calling. she was an evangelist in search of a flock. preaching the bible, spreading the gospel and singing it, too. that's her voice soaring on a recording of her favorite hymn,

"amazing grace." >> giving. constantly giving. >> i have learned some of the best organic food there is to eat. >> she'd walk into burger king, and the waitress would say, "that's a pretty necklace," she'd pull it off, "well, here it is." >> she was the type of person that just gave herself away. we believe in that. that's part of our faith. and shirley was that type of person. >> reporter: shirley prayed with dr. mike the first time they met. he worked much of his life as a sky practice or the, adjusting grateful patients backs in the nearby florida panhandle. known affectionately as dr. michael, he was a from innocent member of the medical community, smiling in the newspaper and online. but money trouble plagued the sky practice or the like a crooked spine and his financial problems troubled shirley's family, because one of her husbands, gene seitz, had died and left her with his name and a

hefty inheritance. $1 million. were you worried about her money? >> yes, i was worried about her money. i mean, he come into her life with the clothes on his back. and he's a doctor? he doesn't have a home, mama? well, he's in transition. he doesn't have a job, mama? well, he's a kchiropractor. he's gonna get a job in alabama. >> he come into the marriage with a wore out pickup truck and a bunch of debt. >> reporter: her engagement ring from dr. mike, the wedding rings. the house they lived in that first big purchase together. the family says, shirley paid it all. mike seemed to appreciate it. women from their church later said michael was a wonderful husband to shirley. >> anything in the world shirley would tell him to do, he'd jump up and do it, you know. but who wouldn't. >> reporter: who wouldn't, because he knew where his bread was being buttered? >> yeah, yeah, you said that, i didn't. >> reporter: love, marriage, and pushing the grandkid's baby

carriage. shirley's family made room for big mike. and even the doubting thomases could not guess "for better or for worse," was about to get a whole lot worse. four years into the marriage, something is wrong with shirley. months later, in a recorded interview obtained by "20/20, " dr. michael would tell investigators shirley had been ill for weeks, food poisoning, thyroid problems and to cap it off, a stubborn migraine headache. >> she gets bad migraines maybe two or three times a year that last three, sometimes four days. >> reporter: shirley's little brother, rickey thomas, her closest sibling, who had even grown to like mike, speaks to her on the phone. >> and i said, "hey, what's going on with you, girl?" she said, "i'm just not well. just pray for me." she was so out of it, she just didn't even want to talk to me. >> reporter: shirley's mom, myrtle, and brother junior thomas, drive five hours south, to the house on camelot, to see what was what. >> i said, come to the door, let us in. she said, i can't get up. i said, what do you mean?

she said, i feel so bad, i can't get up. >> reporter: the family says they'd never seen shirley like this. >> she had a terrible headache. she was really sick. >> reporter: the family says mike tells them shirley might have fallen down these stairs a few days earlier, while he was away. knocking down a potted plant. he later tells investigators too. >> i sat here with her mother and asked her, baby, do you remember falling down those steps, because they plant was knocked over. and she almost got irritate-ly mad at me, and she said, i did not fall. >> reporter: myrtle and mike nurse shirley through the weekend. they try to get her to the doctor, but shirley keeps putting it off. mike gives her migraine medicine. it seems to do a world of good. and by sunday night, shirley is even sitting up, eating and talking. >> i said, now, shirley, you better lay down and go to sleep. we don't want that to start back again. and that's the last words i ever said to her. >> reporter: the next morning, mike, who said he had been

spending his nights on the couch, goes into the bedroom once again. >> and she wasn't responsive. so i walked over and i turned on the light, and her lips were already blue. >> reporter: mike yells for myrtle. >> she's not breathing, call 911. >> reporter: steve brannan is a former fbi agent, now a private investigator hired by the thomas family. he showed us around the house on camelot. so, when myrtle gets in here, what does she see? >> she sees shirley on the floor, by the bed. >> reporter: on the ground? >> on the ground. and michael beginning cpr. >> reporter: myrtle knows it's too late. >> i said, "mike, shirley's already gone." >> reporter: shirley is dead. >> precious. she was precious. if i can be a third of the woman that she was, i'm -- i'm blessed. i loved her. she was my best friend, jim.

>> and she didn't deserve what happened to her. >> reporter: at the hospital, where shirley is pronounced dead, a distraught dr. mike demands answers. >> first thing mike said, i'll never forget it. he said, "well, i want an autopsy." >> reporter: mike says he was desperate to know whether he could have prevented shirley's death. >> i said, i'm trying to get a handle on what's going on, because not only have i lost my wife, but now, i don't know whether i could have saved her, if i could have gotten her to the doctor. >> reporter: and things are about to get worse for the grieving widower. because as they begin to settle the estate, shirley's family turns on him. chester is sorting through shirley's fortune. what's left of it. what happened to her finances? >> he soaked her dry. i don't know another way to put it. >> reporter: still ahead, dr. mike gets his answers. an autopsy reveals the cause of death, and it was no migraine. but was it the other m-word? stay with us.

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>> reporter: it's a southern-fried mystery. a one-time millionaire shirley seitz dies suddenly in what we will soon see may not have been sweet home alabama. her family suspects foul play everywhere they look. and dr. michael wohlschlaeger -- they're looking at you. >> he just didn't act right. to me, he just didn't act right. >> reporter: you started to have questions about what happened to your mother? >> absolutely. i did. absolutely. >> reporter: the suspicions begin with dr. mike's reaction to their surprise visit back when shirley was sick. dr. mike items investigators, in that interview obtained by "20/20," he was happy to see his inlaws. >> i said, "boy, this is just a real godsend." i said, "shirley's been sick for the last three days, with one of her migraine headaches."

and, i said, "here you are, showing up." >> reporter: shirley's mother, myrtle, and brother, junior, say that's not how they remember it. >> he acted very shocked that we were there, and asked me, "what are you all doing here?" >> reporter: the family also wonders about that knocked-over flower pot. >> when we went in, we noticed a flower pot that was laying in the floor and i asked him about that. >> reporter: mike said it showed shirley might have fallen down the stairs a few days earlier while he was out of town at a doctor's appointment. >> he tried to tell us that -- that she had fallen, i guess down the stairs and knocked this flower pot over, you know. and that's how her -- what -- what was causing her head to hurt, you know? >> reporter: but the family suspects that is a little too convenient. they speculate mike was staging things to back up a phony story that shirley had fallen. thomas family investigator steve brannan. >> when the mother comes in on friday, this flower pot that was

supposedly knocked over on wednesday is still knocked over. it's not been setup or cleaned up. >> reporter: it's still there. >> yes. two days later. >> if i turn a flower pot over in my house, i pick it up. i don't let it lay there for two days. >> reporter: something else bothers myrtle. michael's activities on the morning shirley died. on the way to the hospital, myrtle says she told him she noticed a spot, maybe blood, maybe something else, on the bed where shirley had slept. >> i said, "well, i want to know what that red was on the sheet." he said, "there wasn't nothing red on that sheet." >> reporter: whatever it was, the family says, mike was very quick to clean it up. when you got back to the house, did you go looking for the sheets to see what was on it? >> they was done gone. he'd done jerked them off the bed and had them in the washing machine to wash. >> reporter: dr. mike later told police shirley got sick on the bed. hasty laundering, a knocked over plant. somebody not acting right. all suspicious, perhaps, but is

this grieving family overreaching to blame someone? >> we don't like something that's ambiguous, none of us really like that. we want to know why something happened. >> reporter: psychologist jennifer hartstein says in cases like these, it may be the grief talking. >> and very often, while we're grieving, if we're angry, we might want some sort of retaliation, we think that they must have done it, so we're going to retaliate and go after that person. >> reporter: but buckle up, because the thomas family is not going to quit. in fact, their hunt for shirley's will leads to a scene straight out of a tv cop show. while dr. mike is out at a religious meet egg, the family conducts a frantic, clandestine search of the house. mike could have come back through that door at any minute. >> so we was having to kinda sneak around and do what we had to do with one eye here and one eye there. >> reporter: sharon and her uncle take the place apart, drawer by drawer. >> we turned that house upside down.

>> we were digging, digging, taking pictures, trying to find that original will to get in my hand. >> reporter: they find the will, in which shirley, even after four years of marriage, left everything to her daughters. not a dime to her husband. why didn't she write him in? to the family, the answer becomes clear when they find something else. shirley's journals. personal, revealing journals. >> we found it in, actually, up underneath another drawer in her bedroom. >> reporter: and is there anything of interest in the journals about their relationship? >> how much longer am i going to have to financially support this man? he said he wasn't going to do this to me, he was going to get a job. he's constantly spending my money. lord, when is he going to get a job? >> reporter: later, when police ask mike about his marriage, he paints a totally different picture. >> how would you describe your and shirley's relationship? >> we had an absolutely marvelous relationship.

shirley and i were the epitome of just exactly what a husband and wife were supposed to be. >> reporter: but when shirley's daughter reads some of the journal entries to "20/20," well, see what you think about this marvelous relationship. >> nothing but take, take, take from this man. no giving. i'm not a wife. i'm a bank. that is taking care of all of his financial needs. >> reporter: in fact, seven months after shirley's death, she was still helping to support him officially. mike collected on her life insurance. $100,000. all the while, the thomas family is desperately searching for a smoking gun. still ahead, they think they find one. at least, half of one. not the gun, just the smoke. from a suspicious fire in dr. mike's past, and a most curious discovery about the first mrs. wohlschlaeger. like shirley, she's dearly departed. and wait until you hear how she died.

stay with us. we're on twitter tonight and we want to know, based on what you've heard so far, what do you think happened to shirley seitz? is a grief-stricken family making wild claims? or are they really onto something? use #abc2020. something? use #abc2020. we'll be right back. ♪ ♪ ♪

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"20/20" continues. once again, jim avila. >> this is south dakota. >> reporter: shirley seitz dead and gone at age 59, the fifth wife of dr. michael wohlschlaeger. her family, convinced he had something to do with her sudden, unexplained death, searches his long trail of matrimony and comes across the odd tale of wife number one. her name was lynn. >> i said, i need to tell you some things that i've found out about michael. >> reporter: the family had discovered what is to them a very strange coincidence. shirley's daughter sharon arranged to meet her uncle to tell him about it. >> i knew that it would be upsetting, so i had just asked

ricky, let's just ride up to the cemetery. >> reporter: they come here, to of all places, the hike rock cemetery, where they had buried shirley less than two weeks before. >> right beside shirley's grave -- >> reporter: among the shad dopes of the tombstones, it's an oddly comforting place, where they can feel shirley's presence, and where sharon can broach a difficult subject, with the one family member still close to mike. she shows ricky an old, yellowing newspaper article. a brief story about the sudden death of a young woman in gainesville, florida, in 1977. lynn wohlschlaeger, mike's first wife. the article says, "a 25-year-old woman apparently choked to death friday on a throat lozenge." choked to death on a cepacol lozenge, that's what her death certificate says. it appears there was no police investigation. sharon and the rest of the thomas family say they find two things strange about that. first, an otherwise healthy

25-year-old woman choking to death on a cough drop. second, they say michael had always told them a different story. he told them his first wife didn't die suddenly. she died a slow, painful death from cancer. >> michael had told us the entire time that he was married to mama that lynn had leukemia. >> reporter: and that's how she died? >> yes, that's how she died. and that when she died, he was holding her hand, consoling her in the bed. >> reporter: he never mentioned a throat lozenge? >> no. >> it may me wonder, well, what else has he lied about? >> reporter: what else has he lied about? for the answer to that question, we take you to chipley, florida, and a suspicious fire in dr. mike's past. nearly 20 years ago. >> i was approaching this place of business here. i detected smoke, seen smoke. >> reporter: lieutenant tillman mears, in plain clothes now, was a rookie patrolman back in the day. he says dr. michael, as

everyone called him, was the go-to chiropractor in town, especially for female patients. one night, his office caught fire. the doctor was found standing across the street, just watching it burn. >> my first question was, why didn't the doctor call the fire department? >> reporter: instead, he tells an incredible story. someone trying to kill him set the fire while he was trapped inside. >> he said he woke up smelling smoke and had to fight his way out of the burning building. >> reporter: escaping by karate kicking through a burning wall, barefoot. but when police check his feet, there's no burns. not even a scratch. mears says the skillful chiropractor was twisting the truth. >> he thought i was going to go away, i think, and believe what he said. >> reporter: but the cops say dr. mike's story stunk. and so did he. >> once i approached mr. wohlschlaeger, i detected a smell of diesel fuel on his person. >> reporter: and that was before they found the can of diesel fuel and a match.

and the suspected motive. he was flat broke and after the insurance. dr. wohlschlaeger was arrested, tried and convicted of arson. one thing stayed with the policeman all these years -- he says dr. mike threatened him. >> after the jury came back with a guilty verdict, he turned and told me that i'd pay for this. >> reporter: dr. mike was the one who paid, although he got no prison time, just 15 years probation. and with a surrender of his license, it was the end of his career as a sky practice or the. but for shirley's family, it was evidence of much more. dr. mike, when he is broke, they say, is not above committing a crime or inventing a whopper of a story to cover his tracks. >> who had the motive? who had the opportunity? who has lied in the past? >> reporter: trying to answer that question, we contacted mike's second wife, paula. she says he never harmed her. even so, as you've seen, he's no choirboy.

in fact, he's a convicted criminal. but capable of killing? who says? she does. other ex-wives are now coming out of the woodwork with startling stories of their own. all of a sudden? >> bam to the back of the head. >> reporter: you just feel blunt impact? >> just bam. >> reporter: stay with us. about insurance, e makr because what you dont know can hurt you. what if you didn't know that it's smart to replace washing-machine hoses every five years? what if you didn't know that you might need extra coverage for more expensive items? and what if you didn't know that teen drivers are four times more likely to get into an accident? 'sup the more you know, the better you can plan for what's ahead. talk to farmers and get smarter about your insurance. ♪ we are farmers bum - pa - dum, bum - bum - bum -bum ♪ ♪ ♪

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>> reporter: in broad daylight, in the middle of the night. there are a million ways to die. but the criminal justice system really only concerns itself with one -- homicide. that's what the thomas family of alabama suspects happened in the mystifying death of shirley seitz. they accuse shirley's husband, dr. mike wohlschlaeger. >> i intend to see that he's dealt with. and he can take that to the bank. >> reporter: a flicker of suspicion about what happened in the house on camelot court is now a raging five-alarm mission for what they see as justice that has fully engulfed three generations of the thomas family and leads to two more of dr. mike's five wives. >> so, i just get on the internet and start facebooking. >> reporter: relentless, sharon has tracked down yet another wife.

number three, gloria potts. >> and i said, "well, i would like to talk to her. i just want to find out, who is this person that we thought we knew?" >> reporter: gloria says she knows things about dr. mike. >> hey. >> give me a hug. >> reporter: "20/20" was there when gloria met shirley's family face-to-face for the first time. what could have been the most awkward family reunion ever, relatives of the fifth wife meeting the third wife. it's the dr. mike ex-wives club. bonding over their shared suspicion. >> it's so good to meet all of y'all, to be able to let y'all know how i feel and that i'm so sorry. >> reporter: of course, mike is missing. and so is shirley. >> i didn't know shirley, but it was almost like i had lost someone. >> reporter: gloria spoke with sharon by phone soon after shirley's death.

she believes that toward the end of their marriage, michael was trying to poison her. >> i felt like i was being poisoned. i really did. >> reporter: you got sick? >> sick, couldn't hardly move. >> and then that's when i turned around and told her, "gloria, i can't believe you're saying this to me," but i said, "mother has had the same symptoms." >> reporter: the family of wife number five, shirley, wondered if dr. mike had been trying to poison her, too. and you guessed it, here comes mrs. wohlschlaeger number four -- diana. >> today's date is february the 4th, 2011. >> reporter: in a recording obtained by "20/20," investigators question diana yohn, the fourth stop on dr. mike's matrimonial trail. the wife between gloria and shirley. >> i think the man's dangerous, personally. >> do you think that he is capable of murder? >> i don't know. >> reporter: she has no proof,

but diana tells police toward the end of her their marriage, when she had a $250,000 life insurance policy, she suspects dr. mike may have been trying to poison her, too. >> you think he may have been giving you some type of medication but you're actually not sure of that? >> yeah. i mean, it just seems my headaches were so bad, and i get migraine headaches, okay? and it's documented that i do. but they were so bad when i lived with him, i couldn't even work, i could hardly function. >> reporter: near the end of her interview, mike's ex-wife makes a chilling request. >> and i'll be honest with you. if something happens to me, he needs to be investigated. >> reporter: so now two more wives suspect dr. mike was trying to poison them, and one of them says hold on, that's not all. wife number three, gloria, revealed a terrible trauma she says happened in her marriage nearly 30 years ago. she says dr. mike, the man who had always killed her with kindness, tried to kill her with a mallet. >> and i was asleep, and he hit

me in the back of the head with a mallet. >> reporter: with a mallet? >> yes. and all of a sudden, a pillow went over my face and his hand came under the pillow and covered my nose and my mouth. >> reporter: gloria says she escaped by playing dead, and then running out of the house. >> i was hysterical, crying and upset. and when i would try to yell for help, i'd go -- [ whispers ] "help, help!" and i had no voice. >> reporter: you went to the hospital? >> i went to the hospital, but we told them i slipped in the tub. >> reporter: did you ever ask him at any point, "why were you doing that, why did you try to kill me?" >> yes. he told me he had gotten stung by a jellyfish when he worked in china, and that it was a reaction to the toxins. >> reporter: that's right, she says dr. mike's excuse for hitting her over the head with a mallet? the jellyfish made him do it. had there been an argument or something? >> no. >> reporter: so it was just this one time. >> just this one time, he snapped.

>> reporter: gloria says she told no one, not even the police. sticking to the story of slipping in the tub until she and mike divorced, about ten years later. only then, she says, did she begin telling people. she also got a restraining order. so people are going to wonder, okay, so you get hit over the head -- the guy puts a pillow over your head and you didn't goft hdivor right then. you stayed. >> yes. >> reporter: have you asked yourself why? >> a million times, i can't understand why. i have no answer to that question. i'm sorry that i didn't -- >> it's all right. i told you that. >> i really should have called. >> reporter: she says she had two children to think of. and aside from the one incident, mike was never violent. so besides the fact that he hits you with a mallet, he was a good husband? >> other than trying to kill me, to my knowledge, he was a very good husband. it doesn't make sense. and me staying didn't make sense. >> reporter: maybe she's just mad. maybe she is trying to get back at him. >> possible.

that's a possibility. but she had been telling the same story for a number of years. it didn't just come up after shirley died. >> reporter: can you still see him standing over you? >> yes. and i was -- i was terrified. i didn't know what to do. >> reporter: now, remember, when gloria told the family and then police this amazing tale of mike's alleged attack, no one knew what killed shirley. the autopsy was not finished yet. so, imagine the reaction when, months later, the family is finally given the results. >> i'm shaking my head. i can't believe this. i cannot believe this. i can't believe this is happening. >> reporter: why? because the medical examiner finds what caused shirley's death is no migraine. it's a blow to the head. "blunt force head injuries." a hit to the back of the shirley's skull, hard. that is what killed her. so, when you find out, later on,

that it's blunt force trauma to the head -- >> oh. then there's no question in my mind. that michael murdered this woman, murdered shirley. >> my mother has actually been killed. this man has killed my mama. >> reporter: but not so fast. the toxicology report found no poison or fatal doses of drugs. and even as it makes clear the cause of death, the autopsy fails to answer the really big question -- the manner of death, how shirley got that fatal injury. the medical examiner writes simply "undetermined." accident? homicide? can't tell. still ahead, is this case so complicated only a dummy can solve it? when "20/20" continues. >> now that we're further along in the story, have you changed your mind? what do you make of the ex-wi s ex-wives, their stories and that throat lozenge? let us know on twitter, use

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>> reporter: it's a deadly game of 20 questions. perhaps first, does this

stairway lead to accidental death or, as the family of shirley seitz believes, is it a fatal spiral to foul play? >> my theory is that my sister did not fall down the stairs. >> reporter: three people go to sleep in this house on a winter night in alabama. only two wake up. the husband, dr. mike, says maybe his wife fell down the stairs a few days earlier. but no one, not him, not her mother, who was there, saw, or for that matter, heard shirley seitz die. so what happened? >> no better words, slammed my sister's head against a wooden floor, or against something hard, fractured the occipital bone in the back of her head, dislocated her brain from the front of her head, and she died from the results of it. >> reporter: so, is that possible? we summon two top experts. in the field of forensics, a medical examiner. in the field of falling down, a dummy. dr. bill manion, a private medical examiner from new jersey, has conducted

thousands of autopsies. >> very difficult. i mean, this is the kind of case that exasperates pathologists, because we can hear all kinds of hearsay and complaints of family members, but again, to go into court beyond a reasonable doubt this is a homicide, it would be very, very difficult. >> reporter: we asked him to review shirley's case. his most important finding? dr. manion says, in his opinion, the autopsy shows shirley certainly did not die days after falling down the stairs, as dr. mike suggests. she died within hours. do you believe she would be able to carry on a conversation? sit up -- >> no, i don't. >> reporter: couple days later, talk with her mother, sitting on a couch? >> the forensic pathologist thought this was an acute injury, and she died within an hour or two of this injury. that's my read on the autopsy. >> reporter: not days later? >> not days later. that's correct. >> reporter: but does that mean shirley was murdered? not necessarily. we took dr. manion to a house

with a carpet-covered staircase, like the one where shirley lived. an important point -- shirley had only one serious injury, the blow to her head. no bruises on her back or buttocks. so, a full fall down the stairs like this is highly unlikely. it's not consistent with falling all the way down the stairs? >> that's correct. i would expect her to have more injuries if she fell down a flight of stairs. >> reporter: in fact, dr. manion says the only fall on the steps is that if this tripped at the bottom of the stairs. >> as she falls back, she strikes her head on the edge of the step. and by doing that, she sustains all the skull fractures to the back of the head. >> reporter: now, there is at least one scenario in which the autopsy and the family's theory could match. here, in the bedroom. >> in a homicide scenario, you could just lift the person up and then slam them right back on the ground. >> reporter: but dr. manion has

serious reservations. for one thing, shirley could have fallen accidentally and could she have within murdered with her mother right there in the house? >> we don't hear any boom, any commotion. the mother is there, she doesn't hear any screaming. there's no signs of a struggle. so, again, very, very difficult to say this is a homicide. >> reporter: in the end, our expert, dr. manion, says the autopsy does not have all the answers in this case. >> this is the kind of case where you need help from the police. >> reporter: but there was an investigation by loxley police and the alabama bureau of investigation. it went on for a year and resulted in a 184 page report to the prosecutor. although, shirley's family doesn't think much of it. >> i think it's a joke. i think my 10-year-old grandson could have done a better investigation than the a.b.i. done or the loxley police department. >> reporter: for one thing, the thomas family feels agents went way too easy when they interviewed dr. mike. >> do you have any suspicions as to what may have happened to her?

>> the only thing i can rationalize, based on the way she was feeling, and what the autopsy report said, was she had to have slipped down the steps and hit her head. >> reporter: the police do ask mike whether he might have accidentally done something to shirley. >> and you're a chiropractor, right? >> yes. >> you said you worked on your wife? >> yes. >> do you think something might have happened when you were adjusting her or something? or -- >> i've adjusted thousands upon thousands of people, and i've never had -- i mean, my entire career i've never had any malpractice suits, never had any injuries. other than a couple of broken ribs on some old ladies. >> reporter: when the a.b.i. ended its investigation, the county prosecutor took no action. the thomas family is furious. why has nothing happened? >> it's because someone does not want to do their job. they have proven to me -- i'm talking about the baldwin county district attorney's office. that they do not want to work hard on this case. >> reporter: they hire birmingham attorney

henry frohsin, and nearly two years after shirley's death, they sued dr. mike. >> the lawsuit alleges the deceased was killed through the actions -- by the actions, of michael wohlschlaeger. >> reporter: answering the suit, dr. mike flatly denies having a hand in shirley's death. but he didn't even need to bother. that's because the lawsuit was dead on arrival. >> there was one factor that we did not know and didn't appreciate. >> reporter: it turns out shirley's daughter had agreed not to sue mike, and sure enough, the judge threw out the lawsuit, leaving any legal action in the hands of the criminal justice system. still ahead, an unscheduled appointment with dr. mike. you won't want to miss it. >> y you have to know whether or not you murdered your wife.

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>> reporter: shirley seitz is at peace. she's home now in the family plot in blount county, alabama. but her family cannot rest. are you feeling a little frustrated about the fact that dr. mike is still free? >> yes, absolutely. he's living his life. he's going on with his life. he's moved on, like nothing's ever happened. i believe, and i'll go to my

grave believing, that some time between midnight and 7:00, he went in that bedroom and took her life. >> reporter: we tried to make an appointment to see dr. wohlschlaeger, to ask him about his terrible luck, about how and why two of his wives had died early, sudden deaths. and two others suspect he tried to poison them, but the doctor wouldn't see us. turned down our request for an interview. so, we went to see him. we found him living in pensacola, florida. and not alone. dr. mike -- >> whatever you are doing -- >> reporter: the woman with him, and threatening to sue, as i back pedal, used to be known as li luanne elkins. she'd known dr. mike back when shirley was still alive. the question is, just how well? >> i do believe that he was having an affair on mother. the woman that he is now married to, i believe, is the woman that he was seeing prior to mother's

death. >> reporter: married to? that's right. luanne now goes by the name maggie. maggie wohlschlaeger. she is wife number six! >> are you currently in a relationship with anybody else now or -- >> i go out with people just to be with them. >> reporter: her name had come up in dr. mike's interview three months after shirley's death, when police asked about his love life. >> i've been to the movies with luanne, and i've actually babysat at luanne's two sons. not really dating, dating. i mean, i see -- none of them are dates, per se. no, no. >> reporter: dr. mike denied to police that he cheated on shirley. but sharon says she believes it could be another motive for wanting shirley out of the way. >> there's too many red flags with what i have discovered in reference to her.

>> reporter: we found dr. mike in a fast food parking lot. wife number six was not happy to see us. but we did get to ask that critical question. >> you have to know, did you murder shirley? did you murder shirley? >> no, i did not. >> reporter: let me ask you, myrtle, as a mom, what are you looking for her? >> i guess justice. i don't want to accuse somebody of something they didn't do, but if he did do something to my daughter, well, he'd have to pay for it. >> when shirley married this man, she had half a million dollars in liquid as cemesets a home and 15 acres of land. >> reporter: what happened to your sister when the money ran out? >> she died. >> reporter: wohlschlaeger says he is living on food stamps and can't afford a lawyer, although he may need one again. the thomas family, at long last, got some good news. they say the alabama attorney general has reopened the case. the family hoping this painful game of 20 questions is nearly

over. >> i am desperate for someone to answer those questions and give me an answer. >> reporter: the thomases believe this case should not linger. not just for shirley's sake, but out of a new concern. a concern for mike's new wife. in fact, ricky says he's called to warn her. >> i didn't feel like i could rest without at least telling her, and she got very defensive. i said, hey, okay, i'm just calling you to warn you because i wish somebody had warned my sister. >> we had a good trip. good trip. >> reporter: the family says mike may have replaced shirley, but they cannot. any time he needs to remember, little brother ricky drives up to that quiet spot in high rock and listens for the sound he's been missing. his big sister's voice.

♪ amazing grace ♪ how sweet >> i got a cd of her. sometimes i just sit there, listen to her sing "amazing grace." ♪ will lead me home nearly perfect. next the giants pitcher who just missed a place in baseball history.

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