A WOMAN GOES MISSING IN PANAMA, AND LAW ENFORCEMENT OFFICIALS TURN TO A LITTLE-USED FEDERAL LAW TO GET JUSTICE - BUT WILL THEY SUCCEED?

"48 HOURS: DEVIL'S ISLAND"

Tuesday, June 23, 2015 at 10:00 PM, ET/PT

When a California woman goes missing in Panama, her family is determined to prove her ex-Marine boyfriend knows far more than he's saying. Now, her family wants answers and law enforcement officials are relying on a little used federal law to take the case to court. But will there ever be an answer to what happened to Yvonne Baldelli?

Peter Van Sant and 48 HOURS report on the latest, significant turn in the investigation into the death and disappearance of Baldelli and the case against her boyfriend Brian Brimager in an updated encore of "Devil's Island" to be broadcast Tuesday, June 23 (10:00 PM, ET/PT) on the CBS Television Network.

The story began when Baldelli and Brimager moved to a tropical Caribbean island off the coast of 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, told 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.

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

The news rocked Baldelli's family and kicked off a search for the young woman who appeared to have a bright future ahead.

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

The FBI and Panamanian authorities' investigation into Baldelli's disappearance would lead through the swamps of Island Bocas del Toro in Panama and back to San Diego, where they learned Brimager was leading a second life and had gotten married to Kristen Werkhoven.

Brimager was taken into custody in the U.S. in 2013 and charged with obstruction of justice for his attempts to cover up the alleged murder. He was also charged with murder in Panama when Baldelli's remains were discovered not far from where the couple had been living. Then, in April, U.S. officials dropped a bombshell, using a little-used federal law to charge Brimager for Balldelli's murder in the United States even though the crime allegedly occurred in Panama. Brimager pleaded not guilty to the murder charge and all felonies related to Baldelli's death. He is awaiting trial.

Van Sant and the 48 HOURS team travelled to Panama to investigate the case and talk to locals about the couple. Van Sant and the team also confronted Brimager in San Diego. 48 HOURS: "Devil's Island" is produced by Chris O'Connell. Cindy Cesare is the field producer. Suzanne Allen is the senior coordinating producer. Anthony Batson is the senior broadcast producer. Susan Zirinsky is the senior executive producer.

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