jekyll and mr. hyde. >> tell me about your sister. what was she like? >> gail was a very gentle soul. >> gail beth katz was born on march 8th, 1956. the oldest of three children. her family lived in brooklyn, new york before settling on long island. >> i was one year behind gail in school. we were best friends. she was beautiful, smart, and unfortunately anxious. a little bit of depression early in life. she never thought she was good enough. she never knew how good she was. >> reporter: gail hits a low point in 1979 and attempts suicide. >> in my heart of hearts i believe it was more of a really, really big cry for help than a true suicide attempt. >> reporter: over time alayne says gail appeared to bounce back, landing a job at an ad company and building her way back up. >> and that's when one of her friends decides that she's got to introduce gail to dr. robert bierenbaum. >> reporter: robert bierenbaum met gail during his surgical residency in new york. >> he's close to her age, jewish, classical guitar player. he spoke several languages. he was a g

but like the da vinci jekyll system would, ah, no, some of dooley chill out people have always strived for, and hans surgical precision deal using magnifying lenses and microscopes. we cheated an image. it's important because there are surgeries, especially in pediatrics, where you can make a patient and permanently disabled if you miss a cut by a millimeter. or you can give a patient a heart attack by puncturing a tiny vessel with a stitch seal so, so i can speak about that because i have experience all of it as a surgeon or the but the also robot assisted surgery is extremely costly in all respects. will it the robots are expensive, which in burg and operating them is also expensive. in, in the united states which has the highest number of robot assisted surgeries or more people are refusing robotic surgeries for many reasons, which i won't go into yours. lithium in the patients are refusing yet because i mean both patients and surgeons there's a lot of talk about the so called g 5 revelation and they say that it will galas high performers connections never seen before. so that can b

but like the da vinci jekyll system would, ah, no, some of dooley chill out people have always strived for and hands, surgical precision deal using magnifying lenses and microscopes. we cheated an image. it's important because there are surgeries, especially in pediatrics, where you can make a patient and permanently disabled if you miss a cut by a millimeter. or you can give a patient a heart attack by puncturing a tiny vessel with a stitch seal so, so i can speak about that because i have experience all of it as a surgeon or the but the also robot assisted surgery is extremely costly in all respects. will it the robots are expensive, which in barrel and operating them is also expensive. in the united states, which has the highest number of robot assisted surgeries or more people are refusing robotic surgeries for many reasons, which i won't go into years. lithium in the patients are refusing yet because i mean both patients and surgeons there's a lot of talk about the so called g 5 revelation and they say that it will give us high performance connections never seen before. so that ca

jekyll and mr.e. >> as physicians we all take that oath to above all, do no harm. ♪ i love you ♪ >>> in the 1980s, new york city was a very different place. it was a grittier place. it was a dirtier place. there was graffiti everywhere covering all parts of every subway car. >> the homicide rate in the '80s was astronomical. i mean, there was thousands. there was a lot of drug gangs. it was a very violent time in new york, the '80s. >> throughout the city, there were bubbles of safety. on the upper east side, that was one of them. the upper east side was the place where you wanted to live. >> the upper east side was the music to the beginning of "the jeffersons" when it was on tv. ♪ we're movin' on up at the time east side ♪ >> and on east 85th street, in that iconic high rise featured on "the jeffersons," there lived a handsome doctor and his beautiful wife. a young couple with their whole lives ahead of them. >> from the outside looking in, robert and gail bierenbaum should have been the perfect c

>> i can tell you that there was, like, a jekyll and hyde kind of personality.n evil in his eyes at the time he's talking to me. >> hinton took her to a bed and sexually assaulted her. >> at that point i had lost it, and it was painful what he was doing. so i was screaming, "please don't do this to me. please don't do this to me," and crying. >> after the assault, he left tammy in the basement, handcuffed with duct tape on her mouth. >> and at some point i hear his wife. i hear her voice upstairs. and so i begin to make some noise in the basement. >> and she's like, "what is that?" and he kept running to the basement, which was curious to her. so in the meantime, i managed to lick the duct tape off of my mouth so that my mouth was free. and he came down and opened the door yelling at me. and he actually punched me. and i somehow managed to connect with his thumb and i bit him. and then he recoiled because he was in pain bleeding. and his wife came running down the stairs behind him. she sees me. she says, what's going on? i said, gail, it's me, tammy singleton.

jekyll and mr. hyde. >> there were plenty of warning signs. >> bob tried to kill the cat.