A TROUBLED TEEN IS CONVICTED OF A GRUESOME MURDER, NOW SOME OF THE INVESTIGATORS WHO PUT HIM BEHIND BARS WANT TO PROVE HE DIDN'T DO IT

A SPECIAL TWO-HOUR 48 HOURS MYSTERY ON SATURDAY, NOV. 29

Tim Masters is 37 years old, the same age as Peggy Hettrick was when she was murdered in 1987. Hettrick's mutilated, half naked body was discovered in a field in Fort Collins, Colo. and Masters has lived in the shadow of the brutal crime ever since.

At the time, Masters was a teenager with a penchant for knives and drawing graphic images of death and mutilation and he immediately became a suspect, but the case was only circumstantial. Weeks turned into months and months into years, with no arrest. Authorities even planted fake newspaper stories about his imminent arrest in the hopes of goading Masters into doing something incriminating, but to no avail.

Then, in 1997 authorities found a new expert witness, one who put a new spin on the little evidence had. More than 10 years after Hettrick's murder, Tim Masters was convicted - the result of what his attorneys consider to be a single-minded, psychologically relentless investigation by an overzealous cop. And Masters' supporters, including some of the investigators who initially pursued him, believe this case was built not on evidence, but on fear and they've set out to prove his innocence.

It is a search for answers that would take them around the world and expose stunning new suspects. Why wasn't a doctor, who had been arrested as a sexual offender and lived a few hundred yards from where the body was found, never considered a suspect? The new investigation would take almost a decade, but would finally reveal shocking new evidence and an astonishing truth that would change everything.

Susan Spencer reports on 48 HOURS MYSTERY: "Drawn to Murder," Saturday, Nov. 29 (9:00-11:00 PM, ET/PT) on the CBS Television Network. This broadcast is produced by Joshua Yager, Taigi Smith, and Marc Goldbaum. Al Briganti is the executive editor. Susan Zirinsky is the executive producer.