AFTER MORE THAN 20 YEARS, POLICE LOOK INWARD FOR THE KILLER OF A LOS ANGELES NURSE IN "ONE OF THEIR OWN" SATURDAY, MAY 26 (10:00 PM, ET/PT)

CBS News' 48 HOURS MYSTERY delivers a timely update this week to "One of Their Own," a story about the investigation into the murder of Sherri Rae Rasmussen set to air Saturday, May 26 (10:00 PM, ET/PT) on the CBS Television Network. Rasmussen was killed in 1986 and the case sat unsolved until the Los Angeles Police Department began to look at one of their own.

Rasmussen was a nurse and 29 when she was killed. She was found brutally beaten and shot in her Van Nuys, Calif., condominium. At the time, Los Angeles was in the midst of a spike in crime and police dubbed it a case of a burglary gone wrong. The case was unsettled for more than two decades until authorities quietly reopened it and uncovered the details that blew away the original theory.

48 HOURS MYSTERY first brought TV viewers the story in May 2010.

Maureen Maher reports that police missed repeated signals that an LAPD officer was a suspect. However, Rasmussen's father, Nels, was ringing that alarm from the start. The family says they complained that their son-in-law's ex-girlfriend, a female cop, had been stalking Sherri for some time.

"The first weeks, the first five days I mentioned it so many times that he kind of lost his cool with me, saying that there was no need to go there," Nels says about the lead detective in the case. And the family's attorney, John Taylor, calls the 1986 investigation "sloppy, negligent, inept and incompetent."

The new investigation was top-secret until 2009 when Los Angeles Times crime reporters Andrew Blankstein and Joel Rubin broke the story that a well-respected Los Angeles detective, Stephanie Lazarus, had been arrested for the murder. Blankstein and Rubin were also consultants for the program.

Lazarus had held a position in the commercial crimes unit before the mystery unraveled. In this update to 48 HOURS MYSTERY's original story viewers learn Lazarus' fate.

This broadcast is produced by Ira Sutow, Taigi Smith, Greg Fisher, Linda Martin and Avi Cohen. Michael Vele is the producer-editor. Atticus Brady and Bruce Spiegel are the editors. Al Briganti is the executive editor. Susan Zirinsky is the senior executive producer.