CAN A YOUNG ASSISTANT DISTRICT ATTORNEY AND A VETERAN DETECTIVE HELP SOLVE A THREE-DECADE-OLD COLD-CASE MURDER WHERE THERE WERE FIVE POTENTIAL SUSPECTS?

"48 HOURS: JANET'S SECRET"

May 16, 2015, 10:00 PM, ET/PT

Three decades after Janet Walsh was murdered in the bedroom of her home, her family - and the police - never gave up searching for her killer. Can a determined assistant district attorney and a veteran detective, armed with fresh eyes and new forensic technology that didn't exist when Walsh was killed, help solve a case that had five potential suspects?

Peter Van Sant and 48 HOURS investigate the murder of Janet Walsh and the search for her killer in "Janet's Secret," to be broadcast Saturday, May 16 (10:00 PM, ET/PT) on the CBS Television Network.

It's the crime that confounded investigators in Pennsylvania, and despite the usual ebbs and flows with a case, they never gave up. It was the perfect murder for 34 years - and then it wasn't. A virtual time capsule of evidence left from the initial investigation opened up investigators to the world of a young woman whose life was cut short. It was a trip back that uncovered a clue her killer never expected to be found.

Walsh was last seen by friends she had been out dancing with in the early morning hours of Sept. 1, 1979. When she didn't show up for work, her family went to check on her at her home in Monaca, not far from Pittsburgh. She was dead in her bedroom, with her bathrobe tie used to bind her wrists. Walsh had only recently started rebuilding her life after separating from her husband.

Investigators soon had a long list of suspects, including her husband, a lover, a drifter, her employer and a local man.

"I have a plot from an old TV show like 'Murder She Wrote,' where we have five suspects and I can't put a finger on any of them," says Detective Andy Gall, Assistant Chief of Detectives for the Beaver County District Attorney's Office, who, in 1979, was a 25-year-old junior patrolman facing his first homicide.

"Janet was a very, very happy person," says her brother Francesco Caltieri. "And Janet seemingly had everything to look forward in life."

The initial investigation grew cold and no one was arrested. Then, in 2011, a cold case unit interviewed the original suspects once more.

The one-time cold case turned hot when investigators were able to identify DNA on Walsh's sheets, nightgown and bathrobe tie using high-tech tools. The evidence, which had been in police custody, uncovered a bombshell. Police and prosecutors eliminated everyone except Walsh's lover, who few knew about.

But would prosecutors be able to bring Walsh's killer to justice?

Van Sant and 48 HOURS tell the story through interviews with Walsh's family members, those who worked on the investigation, Walsh's husband and several original suspects from 1979. 48 HOURS: "Janet's Secret" is produced by Susan Mallie. Claire Anderson is the associate producer. Anthony Batson is the senior broadcast producer. Susan Zirinsky is the senior executive producer.

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