Scoop: 48 HOURS on CBS - Saturday, November 17, 2012

Highway 16 is an evil road. Since 1969, more than 20 girls and women have been killed or disappeared along the lonely but majestic stretch of pavement in rural British Columbia, Canada. To locals, the road is now known simply as "The Highway of Tears."

Maddy Scott may be one of the haunted roadway's many victims. On May 28, 2012, the pretty, vivacious 21-year-old went to a party with 50 others at Hogsback Lake, not far from the highway, only to never been seen again. Just six months earlier, in the same town, 15-year-old Loren Leslie's mutilated body was found on a logging road not far from Highway 16. Leslie was brutally beaten and molested.

There are signs all along Highway 16 warning women not to hitchhike because a killer might be on the loose. But the murders have not ceased. It's the kind of crime spree that hits police investigators in the gut.

"Unfortunately, they are the toughest cases you can imagine, girls that are last seen sticking their thumb out on the highway and never to be seen again," Royal Canadian Mounted Police Sergeant Wayne Clary tells Peter Van Sant in 48 HOURS: ‘Highway of Tears," to be broadcast Saturday, Nov. 17 (10:00 PM, ET/PT) on the CBS Television Network. "Potentially there is a serial killer," Clary adds.

48 HOURS was granted unprecedented access to the Royal Canadian Mounted Police "Highway of Tears" and Maddy Scott investigations. Van Sant went inside the RCMP to see firsthand how the organization is searching for Scott, as well as for justice in the other unsolved cases along the roadway. Maddy and Loren's families also spoke to 48 HOURS about their daughters.

There have been some answers, but not enough. Police arrested 20-year-old Cody Legebokoff in Leslie's murder. A patrolman pulled him over, thinking he was poaching game. He had Leslie's ID in his truck. Her body was just down the road. Legebokoff has since been identified as the alleged killer of three others, though police have not revealed how they've connected him to the murders that occurred in 2009 and 2010. Still, because of his age, police know Legebokoff couldn't be responsible for all of the murders along the Highway of Tears.

Just two months ago, officials at the RCMP got a break in some cases thanks to updated technology that was able to link DNA samples from one of the highway's victims, Colleen MacMillen, found murdered in 1974, to Bobby Jack Fowler.

Fowler's last victim survived, and gave her first interview to 48 HOURS. "He was weird, he just got weird and he put the rope around my foot," the woman tells 48 HOURS of her night with Fowler. "He told me that he was going to put me in the ocean. I was just trying to scream and he covered my mouth." She survived by jumping out of a second-story window.

Police also believe Fowler, who lived a nomadic lifestyle, may have killed as many as 20 people in the United States and Canada, leaving his own trail of tears in the United States that stretched all the way from South Texas to the Pacific Northwest.

48 HOURS: "Highway of Tears" is produced by Paul LaRosa, Clare Friedland and Alec Sirken. Ryan Smith is the field producer. Peter Schweitzer is the senior producer. Al Briganti is the executive editor. Susan Zirinsky is the senior executive producer.