Oct. 6, 2005 -- -- Nestled in the heart of California's idyllic wine country, the city of Napa is nothing if not a safe place to live. Before last Halloween night, the town hadn't seen a murder in more than two years.
But on Oct. 31, 2004, that tranquility was shattered. An intruder slipped into a home, brutally stabbed two 26-year-old roommates to death -- and vanished.
A third roommate was left alive. She saw the slayings' aftermath, and for months afterward, lived in a state of terror. She spoke publicly about that night for the first time with "Primetime" co-anchor John Quiñones.
"Still I can't sleep," said Lauren, who asked that her last name be withheld. "Basically -- it was a horror movie. That's what I thought -- exactly what I thought when I was up there."
For nearly a year, police had no idea who the killer was -- until last week, when the smallest of clues turned them on to the most unexpected of suspects.
With nothing resembling a nightlife, Napa was an unlikely choice for three single, attractive, career-oriented women in their 20s.
But that was where Lauren, an all-state athlete with a political science degree, and Adriane Insogna, a civil engineer with the city's sanitation district, chose to begin their careers.
They got along so well that in early 2004, they decided to rent a house together on the west side of town. On the day they moved in, Insogna's friend Ben Katz helped out, and her other friends, Lily Prudhomme and Eric Copple, joined them for an impromptu celebration.
Later in the summer, Leslie Mazzara, a bubbly former beauty queen from South Carolina who worked as a public relations specialist, became their third roommate.
The trio settled in comfortably. However, on Oct. 28, there was a ripple in the serenity. Mazzara brought home a boyfriend in the middle of the night, and kept her roommates up with the sounds of lovemaking.
He was the first member of the opposite sex any of them had brought home for the night, and after some discussion, they eventually agreed it would be tolerated.