"48 HOURS" GOES INSIDE THE MIND OF A SERIAL RAPIST HUNTING HIS VICTIMS WHILE TWO DETECTIVES WERE HUNTING HIM

"Hunted" Airs Saturday, Sept. 16

Maureen Maher and 48 HOURS go into the mind of a serial rapist in Colorado and deep into the race to catch him before he could strike again in "Hunted," to be rebroadcast Saturday, Sept. 16 (10:00 PM ET/PT) on the CBS Television Network.

It's a gripping story of a rapist preying on women, young and old, in multiple states and over a period of years, and the tension-filled search to stop him before his victim count grew. Maher and 48 HOURS get inside the investigation with the detectives from two departments - along with the FBI - who pieced together the assailant's trail through smart policing, collaboration, and luck.

"I definitely felt like we were up against the clock," Detective Stacy Galbraith tells 48 HOURS. "It was ticking. I could hear it. I could feel it."

Someone was stalking and raping women in Golden, Colo. He was plotting their schedules. He was even in their homes without attacking them. But when he attacked, he did so with military precision - he raped them, he photographed them, and then he made them shower or bathe as a way to clear out any evidence. Galbraith got the case in 2011, when presented with a brutal rape. The rapist wore a mask and was meticulous in not leaving behind any physical evidence. Shaken, Galbraith described it to her husband, a police officer in a nearby town. Turned out, his department had a similar case.

Galbraith shared her information with Westminster, Colo., Detective Edna Hendershot, and they agreed to work together. In comparing details of both attacks they realized they were on the trail of a serial rapist, one who most likely would strike again... and soon. After finding yet another nearby case involving the rapist, their investigation identified a white truck near two of the crime scenes.

"I just knew in my heart that that was - that was it," Galbraith says.

She was right. No one could have predicted what would happen next. The truck tracked back to 32-year-old Army veteran Marc Patrick O'Leary, who was eventually arrested at his home. The investigation would give the detectives a glimpse inside the mind of a serial rapist they could never have imagined.

"If you want to find targets, you know, you have to learn how to hunt, hours and hours and hours, walking around various different apartment complexes," O'Leary says.

Maher also talks with a woman who was dating O'Leary at the same time he was allegedly committing the crimes. "He was pretty chivalrous and protective," she says. "He was very charming. He was really fun to talk to. We talked for hours at a time quite frequently. There was a lightness to him even though he had a dark sense of humor."

The broadcast also features the heartbreaking story of a woman who was raped when she was 18, though police didn't believe her story. She eventually recanted and was fined for filing a false charge. However, Galbraith and Hendershot's detective work uncovered startling evidence that she was telling the truth.

48 HOURS: "Hunted" is produced by Chris O'Connell, Lauren Clark and Lindsey Schwartz. Greg McLaughlin is the producer-editor. George Baluzy and Mike Mongulla are the editors. Linda Martin is the update producer. Patti Aronofsky is the senior producer. Susan Zirinsky is the senior executive producer.

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