A COLD CASE THAT COPS ARE DETERMINED TO CRACK: A Missing Wife, A Husband on the Run with Their Kids, A Sting Operation, and an Unlikely Second Suspect in the Family "48 HOURS MYSTERY," SATURDAY, JAN. 6

Perry March had the perfect life -- a successful lawyer living in the lap of luxury in sunny Mexico with his second wife, in a peaceful home, complete with a swimming pool where the kids liked to do cannonballs. March had only one problem - a determined cold case unit that wanted to know what happened to Janet March, Perry's first wife, who was reported missing in the summer of 1996, in their hometown of Nashville. Correspondent Bill Lagattuta explores the cold case that took authorities across the border to build a case complete with hired hits, secret recordings, and a tell-all confession. 48 HOURS MYSTERY: "Endgame" will be broadcast Sat., Jan. 6 (10:00 -- 11:00 PM, ET/PT) on the CBS Television Network.

When Janet disappeared in 1996, Perry claimed she left their home willingly and he had no idea where she went. He said he thought she might be relaxing in a hotel somewhere. He only reported her missing after Janet didn't show up for their son's birthday party on Aug. 27. She had been gone since Aug. 15.

Perry later moved on, boasting about his perfect life in Mexico. "I have a great family. I have a great dog," he said, smiling.

The cops never bought Perry's happy story, however, suspecting that something horrible happened to Janet that summer. "His arrogance was like he was laughing at us," said Pat Postiglione, a detective on the case.

Nine years after the disappearance of Janet, cold case cops still had no trace of her body and no information indicating that she was even dead. But they believed their evidence wasn't going to get any better, so they decided to go after Perry with their best shot.

The cops worked with Mexican authorities so Perry could be deported from Mexico, brought back to Nashville, and charged with his wife's murder.

In an interview with 48 HOURS in 2002, Perry explained that after Janet went missing, he called his father, Arthur March, in Mexico, told him Janet left and asked him to come help with the kids. But what cops didn't know at the time was that Arthur was prepared to do just about anything for his son.

After Perry was incarcerated awaiting trial, police got a stunning break in the case. Perry made an unlikely friend on the inside, and a nine-year-old mystery finally began to unravel. They were certain that Perry had murdered his wife. The question soon became, did Perry have help staging a cover-up after his wife's death? And there was one more twist. While in jail, was Perry now plotting another murder, this one with the help of his father?

48 HOURS MYSTERY: "Endgame" is produced by Deborah Grau. The senior producer is Peter Schweitzer. The executive editor is Al Briganti and the executive producer is Susan Zirinsky.