"48 HOURS" INVESTIGATES TWO MYSTERIOUS DEATHS IN A SATURDAY NIGHT DOUBLE FEATURE

"Mystery at Eagle Creek" - 9:00 PM

"Who Killed Fabio?" - 10:00 PM

48 HOURS investigates two mysterious deaths in a Saturday night double feature to be broadcast Saturday, Sept. 8 (9:00 PM; 10:00 PM) on the CBS Television Network.

At 9:00 PM, Peter Van Sant and 48 HOURS investigate the death of Rhonda Casto, who died during a hike with her boyfriend, Stephen Nichols, in Oregon's Columbia River Gorge in an encore of "Mystery at Eagle Creek." At the time of her death in 2009, Casto was a 23-year-old mother of a 9-month-old girl. Somewhere along the trail, she slipped or fell, falling 150 feet before hitting solid ground. Investigators maintained Nichols pushed Rhonda to her death.

The investigation into what happened raised questions about the couple's relationship, allegations of a love triangle and strained family dynamics. In an interview with 48 HOURS, Nichols raised even more questions about what happened that day. After she fell, Nichols said, he climbed down the 150-foot cliff to reach her. In an interview with Van Sant, Nichols compared Casto to a wounded soldier. Asked whether Casto was alive when he got there, Nichols was even more elusive, and the interview took a bizarre turn.

"Did you put Rhonda out of misery that day?" Van Sant asked.

"Let me ask you," Nichols responded, "if you shoot your war buddy because you see how much pain he's in, is that murder?"

"What do you say?" Van Sant asked.

"I say no. Course not," Nichols said.

Julia Simmons, Casto's mother, believed Nichols killed her to collect on a $1 million life insurance policy. "People that have to make up lies are, you know, you can obviously tell that they're guilty," Simmons said.

What really happened on the hike?

At 10:00 PM, Michelle Miller and 48 HOURS investigate the murder of hairstylist and beauty company executive Fabio Sementilli in an encore of "Who Killed Fabio?"

It is a case right out of a primetime crime drama, but it is real. After Sementilli was found stabbed to death, police scoured surveillance video from his Los Angeles neighborhood. Cameras caught the suspects on video running to his home - and then leaving in his Porsche 35 minutes later. While there was video, the suspects identities are hidden.

At first, police believed Sementilli was the victim of a notorious wave of crimes known as knock-knock burglaries, targeting Los Angeles celebrities.

Police would learn that the reason behind the murder was much darker and twisted than a simple robbery. Turns out, it wasn't a break-in gone wrong that led to Sementilli's death after all. Nearly five months later, a pair of arrests would shake Sementilli's family to the core.

How did the respected businessman and industry icon end up a murder victim?

48 HOURS: "Mystery at Eagle Creek" is produced by Susan Mallie and Jennifer Terker. Michelle Fanucci is the development producer. Mike Vele, Ken Blum, Richard Barber and Diana Modica are the editors. Linda Martin is the update producer. Anthony Batson is the senior broadcast producer. Nancy Kramer is the executive story editor. Susan Zirinsky is the senior executive producer.

48 HOURS: "Who Killed Fabio?" is produced by Chuck Stevenson and Greg Fisher. Gabriella Demirdjian is the field producer. Michael Baluzy, Grayce Arlotta-Berner and Jud Johnston are the editors. Linda Martin is the update producer. Patti Aronofsky is the senior producer. Nancy Kramer is the executive story editor. Susan Zirinsky is the senior executive producer.

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