. >> fbi agent mike mccomas grew up along a river in tennessee.g were to float on downstream, it had to be dropped in the middle of a river. mccomas suggested the bridge stakeouts. >> we looked at remote places, dark places. we believed it would be at nighttime as opposed to daytime. >> the fbi and police began night watches at 14 bridges over the chattahoochee and south rivers. the stakeouts were to last four weeks. nothing until the very end. >> we at that point were ready for that to be our last night. and wayne williams showed up. that night. >> just before 3:00 a.m., the station wagon drove onto the bridge. >> had he waited a couple more hours we might not have been there. >> otherwise, we would have missed him. >>> next, the night on the bridge. >> you said, i know this is about those boys, isn't it? >> correct. that's what i said. >> pretty damning statement, don't you think? [ male announcer ] a body at rest tends to stay at rest... while a body in motion tends to stay in motion. staying active can ease arthritis symptoms. but if you have

>> remember what fbi agent mike mccomas said he saw when he got to the scene? >> saw a black male. he had on a baseball hat. >> this is the sketch provided by the witness who saw lubie geter talking to a man the day lubie disappeared and died. mccomas had never seen this until we came back to show it to him nearly 30 years later. >> this is a real strong resemblance to the person that i talked to, wayne williams. he had on a baseball cap. his hair was in an afro. so this just looks like him. >> williams agreed to let mccomas search his station wagon. on the floor, in the front of the back seat, he saw -- >> there was a nylon cord. the best that i could describe the nylon cord was a ski rope type, the woven type. and it was my guess about 24 inches long. >> no. >> williams denies there was any such cord. >> because if that rope had been in the station wagon that night, i'm sure they would have taken it. >> the fact that i didn't confiscate it doesn't make it go away. it was there. >> the nylon cord would never be seen again. >> could have been the murder weapon, as far as i knew. >>