WHO WANTED ARIZONA ENTREPRENEUR AND LAS VEGAS GAMBLER GARY TRIANO DEAD? HIS EX-WIFE, SOCIALITE PAMELA PHILLIPS, SPEAKS OUT FOR THE FIRST TIME AND PROCLAIMS HER INNOCENCE IN "48 HOURS: THE HIT" SATURDAY, OCT. 11, 2014 10:00 PM ET/PT

Colorful entrepreneur and Las Vegas gambler Gary Triano finished up a round of golf at the exclusive La Paloma Country Club in Tucson, Arizona, and headed to the parking lot. Little did he know those moments on Nov. 1, 1996, would be his last on Earth. When he slipped into his car it exploded. He was dead.

Peter Van Sant and 48 HOURS investigate who wanted Triano dead and have the only network television interview with his ex-wife Pamela Phillips, in "The Hit," to be broadcast Oct. 11, 2014 (10:00 PM ET/PT)
on the CBS Television Network.

"I immediately thought - who is it that he hadn't paid," Phillips tells 48 HOURS. "Before the bombing Gary was totally in fear - going around with a gun. He had life threats, I had life threats, the children had life threats - we're talking about Mexican mafia people you don't cross, there was serious, serious things going on."

The Trianos were once a power couple. He was a hugely successful financial developer and made a fortune in the tribal gaming business. When the couple first met, Gary told Pam he was worth in the high millions, according to Pam's friend Laura Chapman. The Trianos were part of the local social set and hobnobbed with the likes of Donald Trump and his then-wife Marla Maples.

Then the bottom fell out. Gary was pushed out of the tribal business and was sent on a downward spiral. The income loss, along with his own gambling problems, put a strain on the couple. He owed $1.8 million to one Las Vegas casino and hundreds of thousands to a group of Mexican investors, according to private investigators. The Trianos separated in 1993 and eventually divorced.

"Gary had very big personality," Chapman tells 48 HOURS.

But who wanted him dead bad enough to place a pipe bomb in a duffle bag on the seat of his car?

Dr. Lawrence D 'Antonio, who knew Gary since they were kids, says he saw a list of names, a hit list, "and Gary Triano was at the top."

Triano was "rotten to the core. He was a con man... .he was a thief who would rob or steal from anybody... including his own family, his own wife," D 'Antonio says.

"It was quick, it was calculated and it was murder," Bureau of Alcohol, Tobacco, Firearms and Explosives agent Tom Mangan tells 48 HOURS of the bomb that killed Triano.

What wasn't quick, however, were finding answers to what really happened to Gary Triano. The unusual story, filled with endless leads and curious characters, kept police searching for Triano's killer for 18 years. Anything was possible. Was Triano the victim of a mob hit? Were any of Pam Phillips' friends involved? Or was the killer closer to home?

Van Sant and 48 HOURS investigate the Triano murder through interviews with Phillips and her attorney, friends of the couple, investigators, ATF special agents and prosecutors.

48 HOURS: "The Hit" is produced by Chuck Stevenson and Greg Fisher. Al Briganti is the executive editor. Susan Zirinsky is the senior executive producer.

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