AN EX-MARINE WITH A SECRET LIFE HAS A GIRLFRIEND WHO GOES MISSING IN PANAMA - WAS IT MURDER?

"48 HOURS: DEVIL'S ISLAND" - SATURDAY, NOV. 15, 2014 AT 10:00 PM, ET/PT

Peter Van Sant and 48 HOURS travel to Panama to investigate the disappearance and death of a California woman who moved there with a boyfriend who turned out not to be as perfect as he seemed, in "Devil's Island," to be broadcast Saturday, Nov. 15 (10:00 PM, ET/PT)
on the CBS Television Network.

Looking for a fresh start, Yvonne Baldelli and her boyfriend, Brian Brimager, moved to the beachside community in Panama. He was an ex-Marine trying to make a go of it as a bar singer. She planned on making bathing suits and selling them to tourists.

"That's where Yvonne wanted to be - it was perfect," Baldelli's sister, Michele Valenzuela, tells 48 HOURS.

Indeed, Baldelli routinely described a life of bliss in Panama in frequent emails to family members. But then the emails stopped. And about a month after the last email, Valenzuela got a text from Brimager saying he was back in the United States without Baldelli. In an email sent earlier, that Valenzuela had overlooked, Brimager wrote he and Baldelli had broken up after she found out Brimager had a child with another woman.

The news would rock Baldelli's family and kick off a search for the young woman who appeared to have a bright future ahead. Instead, they would face driving a two-country investigation into the disappearance - and ultimately, the death of Yvonne Baldelli.

"There's no book for this," Valenzuela tells 48 HOURS. "There's no book for dummies on what to do when your sister has gone missing."

The police investigation would lead through the swamps of Panama and back to San Diego, where they learned Brimager was leading a second life and had gotten married. Baldelli's family also learned Brimager and Baldelli were not as happy as suggested. There were stories of heavy drinking and fighting.

"I call it Devil's Island, because some terrible things took place on that island," Baldelli's father, Jim Faust, tells 48 HOURS.

"Brian Brimager has done nothing, zero, to help with the search for Yvonne," Valenzuela says.

"My sister went down to Panama with Brian," Valenzuela adds. "Brian returned and my sister didn't."

"He came back and he got engaged and got married," says Baldelli's mother, Lillian Faust. "And his life is going on like normal. And our life will never be the same."

A hunch about the origins of an email allegedly from Baldelli set Valenzuela on a mission to prove Brimager had murdered her sister.

Van Sant and the 48 HOURS team travel to Panama to follow police searching a swamp for Baldelli's remains and talk to locals about the couple. Van Sant and the team also confront Brimager in San Diego, where he lives with his wife and child. Will he talk?

48 HOURS: "Devil's Island" is produced by Chris O'Connell. Anthony Batson is the senior broadcast producer. Susan Zirinsky is the senior executive producer.

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