COMING UP ON 48 HOURS MYSTERY: A YOUNG WOMAN IS CONNED BY HER BOYFRIEND, THEN DISAPPEARS "THE STRANGER BESIDE ME" SATURDAY, APRIL 14 (10:00 PM, ET/PT)

WHAT: On March 18, 2010, Jamie Laiaddee vanished from her home in a suburb of Phoenix, Ariz. Her live-in boyfriend Bryan Stewart told everyone she had moved to Denver to take a new job. But when detectives started searching for Jamie, they discovered that Bryan was a con man, and suspected he was also her killer.

WHO: Jamie, a graduate of the University of Michigan, moved to Phoenix and got a high-paying job in medical sales. When she joined a local university alumni group, Jamie fell for a handsome young member named Bryan Stewart. The couple dated for a year and lived together for two. Then Jamie went missing. While searching for her, detectives found evidence that Bryan had been lying to Jamie, and police, about who he is. Bryan is actually Rick Wayne Valentini. Ten years ago he changed his identity illegally, and moved from Michigan to Phoenix to "start over." But the life he left behind led detectives to suspect that Bryan is more than just a con man. In his only interview, the man who insists he is Bryan Stewart talks with 48 HOURS MYSTERY correspondent Erin Moriarty about changing his name, his relationship with Jamie and his claim that he helped her disappear. The broadcast also features exclusive interviews with Jamie's family and friends, Bryan's aunt and daughter, and lead investigators in the case.

WHEN: Saturday, April 14 (10:00 PM, ET/PT)

WHY YOU SHOULD WATCH: When Jamie Laiaddee vanished in March 2010, detectives suspected her boyfriend of killing her, but had no body or crime scene to prove it. The case went to trial based on circumstantial evidence. Stewart, who continues to plead innocence from behind bars, tells 48 HOURS MYSTERY correspondent Erin Moriarty what he claims really happened to Jamie in "The Stranger Beside Me."

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