"48 HOURS" INVESTIGATES THE MYSTERIES BEHIND A MISSING DAUGHTER AND A MURDERED MOM IN A SATURDAY NIGHT DOUBLE FEATURE

48 HOURS investigates the separate mysteries behind a missing college-aged daughter and a murdered mother in a Saturday night double feature to be broadcast August 8 (9:00-11:00 PM, ET/PT) on the CBS Television Network.

The back-to-back editions of 48 HOURS gets underway at 9:00 PM with an encore of "The Lost Daughter," featuring Tracy Smith and 48 HOURS' investigation into the search for Tiffany Sessions, a Florida college student who went out for a walk in 1989 and never returned. The disappearance launched a massive search - driven by her father, marketing executive Pat Sessions - that continues today. Members of the Alachua County Sheriff's Office have not given up, and believe they have a link to the disappearance.

The 48 HOURS team has been reporting on Sessions' disappearance for more than six years, and was there when members of the Alachua County Sheriff's Office excavated the trees and underbrush where another student was found dead 22 years earlier. Police believe the same site was a serial killer's burial ground.

Meanwhile, at 10:00 PM, Peter Van Sant and 48 HOURS investigate the murder of Vanessa Mintz, a mother, wife and businesswoman who was gunned down in a family-owned mountain lodge in North Carolina, in an encore of "The Ultimatum."

The murder left Mintz's family stunned and a town fearing a killer was on the loose. The investigation into what happened to Mintz would expose a hidden secret and her two daughters, Jessica Freeman and Andrea Little Gray, would emerge as powerful advocates for their mother.

Vanessa Mintz was working the night shift at the Saluda Mountain Lodge on Feb. 19, 2011. Mintz routinely texted or called her daughter, Jessica, but on that night she didn't. When Jessica arrived that morning, she found the door to the lodge open. She also found her mother on the bed in a back bedroom. She'd been shot twice. The killer took only $200, but left behind other valuables. Whoever did it, though, also got sloppy. Police found a piece of crucial evidence that only the killer could have left behind.

Travis McGraw, Mintz's husband, a police officer who was also in the Air Force Reserve, said he was 12 miles away from the lodge visiting his teenage son from a previous marriage when Vanessa was killed. McGraw told police he had nothing to do with the murder and willingly turned over his cache of guns to police. However, it was what was found in McGraw's cellphone records - intimate texts to Mary Beth Fisher, who he was secretly dating - that took this case in a very different direction.

48 HOURS: "The Lost Daughter" is produced by Chris Young Ritzen and Tamara Weitzman. Aimee deSimone is the associate producer. Joan Adelman, Gary Winter and Doreen Schechter are the editors. Suzanne Allen is the senior coordinating producer. Kate Harrington is the update producer. Peter Schweitzer is the senior producer. Susan Zirinsky is the senior executive producer.

48 HOURS: "The Ultimatum" is produced by Alec Sirken, Elena DiFiore and Michelle Feuer. Ken Blum and Mike Mongulla are the editors. Suzanne Allen is the senior coordinating producer. Kate Harrington is the update producer. Anthony Batson is the senior broadcast producer. Susan Zirinsky is the senior executive producer.

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