'People Magazine Investigates' Returns This Summer with 'Captivating' New Episodes

People Magazine Investigates will return for its seventh season in July with a “captivating” new lineup of true crime mysteries, including a two-hour premiere on the brutal 1977 murders of three Oklahoma girl scouts attacked at summer camp.

The new season debuts Monday, July 10 at 9/8 CT on Investigation Discovery.

The "chilling" premiere "delves into the 1977 brutal assault and murder of three Oklahoma Girl Scouts away at summer camp: Lori Lee Farmer, Doris Denise Milner and Michele Heather Guse," the network says in a press release.

"The case dominated national headlines for more than a year as law enforcement scrambled to find answers," the press release continues. "PEOPLE’s reporting team takes viewers through the twists and turns of this case, from how local authorities zeroed in on a suspect (a prison escapee with a dangerous past), the all encompassing manhunt to track him down and the subsequent trial that led to heartbreak for the victims’ families and many unanswered questions."

The episode will feature "an exclusive emotional, new interview with Lori Lee Farmer’s parents and siblings, as well as testimony from jurors on the trial and experts close to the case," the network says.

The new season also includes episodes on the I-70 killer, the disappearance of Mark Himebaugh and exclusive new details surrounding the mysterious search for Karlie Gusé, who has been missing since 2018.

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Other episodes of the new season of People Magazine investigates include the disappearance of Tanya Kach, who was kidnapped at 14 and escaped more than a decade later, the 1991 “The Yogurt Shop Murders,” when four girls were killed inside a yogurt shop in North Austin, Texas, and the Brighton Ax Murder, a 1982 murder which took more than 40 years to solve.

Investigation Discovery says "the series will continue to heighten PEOPLE’s acclaimed original reporting on some of the nation’s most shocking cases and unsolved mysteries and expand on them with unprecedented access, fresh insight and powerful perspectives.”

“People Magazine Investigates shines a spotlight on some of the most horrifying crimes that have gripped the nation in recent memory,” the network continues, adding that “each episode continues to offer exclusive interviews with those closest to these crimes, incredible archival footage and emotional, firsthand accounts from victims’ loved ones and survivors.”

New episodes of People Magazine Investigates will air every Monday this summer, starting July 10 through September 11.