The FBI's elite BAU will track down the people responsible for a mass murder after they discover frozen bodies in Nevada during the next all-new episode of "Criminal Minds."

More details have been released about the upcoming episode of the long-running police procedural series. "The Forever People" is scheduled to air on Jan. 14, 2015. According to CarterMatt, CBS also released a press release with the official synopsis, which reads as follows:

"When frozen bodies are found in Nevada floating in water, the BAU's investigation leads them to suspect that the victims were part of a cult that could be behind the deaths. Also, JJ (A.J. Cook) confronts old demons from her abduction and torture last year. Grant Show guest stars. Faran Tahir returns as Tivon Askari, who abducted JJ last year."

Executive producer Erica Messer also revealed that one storyline will center on JJ and the distress she endured when she was kidnapped last season in the epic 200th episode. It will be an emotional storyline as JJ struggles with painful memories one year later. However, because she has internalized the trauma, she will suffer from post-traumatic stress disorder, which will resurface in different ways.

"It's coming out in unexpected ways. She's kind of internalizing it," Messer said, according to TV Guide.

Although her PTSD doesn't affect her job performance, it causes concern among her colleagues.

The producer also teased that JJ will turn to Spencer Reid as her "sounding board" in order to cope with her tragedy and get through it. 

"I've always loved their friendship and this will bring them closer together," Messer said during a recent interview with TV Guide.

In other news, CBS has given Messer the green light to launch another "Criminal Minds" spinoff series, reports Deadline. Based on the veteran crime drama procedural, the spinoff will focus on a different division of the FBI and feature FBI agents who help American citizens in danger in other countries. The show will begin filming in mid-February.

Season 10, Episode 11 of "Criminal Minds," "The Forever People," will air on Jan. 14, 2015, on CBS.