extra." i'm craig melvin. detective donna velasquez was laser focused on finding david jackson's killer, working around the clock, the relentless investigator had tracked down a woman who had claimed david's killer had confessed to her in horrifying detail. the 15-year-old cold case was now red hot and there was about to be an astonishing new wrinkle. was david's murder a family affair? once again, here's keith morrison. >> david jackson was murdered the in 1988 in florida. that much detective donna velasquez could say for certain. but the rest? after more than a year of phone calls and late nights, all velasquez had come up with an increasingly complicated web of stories and relationships. david jackson was married to barbara britton, her father, harry, disliked david. barbara went on to become the fifth wife of a man named michael wolf.