For San Francisco Fire Department paramedic Shannon Stabile, June 2, 2007, started out like any other.

"It was just a typical San Francisco day, where the fog is really dense but the air is really crisp and clean. Saturday morning, typically what you do is you find your open coffee shop, go grab a cup of coffee," she said. "Then the tones go off. OK. We gotta go. So we grabbed our coffee and off we went."

"It was kind of foggy and I'm always a little foggy in the morning. I remember enjoying the coffee," added paramedic Kris Moore. "I think we even said to each other it was time to wake up."

Stabile said police tape was already up when they arrived at the scene.

"As we were walking up to the house, the wind started to blow. As soon as I hit the door, the smell was very distinctive, because blood smells like iron. It hit me like a wall. And there was so much of it," she said. "It was just unbelievable the amount of blood. I had never seen anything like that… I couldn't imagine what his last moments were like."

"We were only in the house - I'm not even sure we were there for a minute. And it was kind of hard to put together what had happened," said Moore.

"You can see when he started to pass out, because the hand prints and smears are going down the wall because he's falling backwards. It was very sad because you could tell he was grabbing at anything," Stabile said. "That was the most unusual crime scene I had ever seen. And I did deem it as a crime scene."

News report: 36-year-old Hugues De La Plaza's family and friends refuse to believe he killed himself… de La Plaza, a French-American citizen, was stabbed three times after coming home from a neighborhood bar… His door was locked, no sign of a struggle, no weapon was found.

"Hugues was the love of my life," said Melissa Nix, a former girlfriend of Hugues de la Plaza. "Once you fall in love with somebody, there's always a part of you that loves that person."

"Walking into that crime scene, anyone with any kind of experience would not ever think that was a suicide," Nix told "48 Hours Mystery" correspondent Maureen Maher. "The Medical Examiners report determined that Hugues died of stab wounds. She was not able to determine whether they were self-inflicted or if he was stabbed by somebody else."

"I did not call this a suicide at the scene," said Assistant Medical Examiner Dr. Venus Azar. "In fact, I remember saying, 'This is a homicide.' I've been swayed back and forth because none of this makes sense. Who would want to kill this guy? What's the motive? It wasn't robbery. There's no evidence of a struggle."

"My gut tells me it's a crime of passion," Nix said. "Hugues was dating a lot of different women and maybe not using a lot of discretion about who he dated."

"Things that you wouldn't expect to happen can and do happen. People can spontaneously decide to kill themselves," said Azar.

Said Nix, "Hugues De La Plaza was murdered."