'Criminal Minds' season 12 episode 17 spoilers: Worse things will come for Reid in prison; Derek Morgan visits BAU in finale

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Unfortunately, more bad things are coming to Spencer Reid (Matthew Gray Gubler) in prison. Meanwhile, Morgan (Shemar Moore) returns to the BAU one last time.

On the next episode of "Criminal Minds" season 12, titled "In the Dark," Rossi (Joe Mantegna) and his team will be dealing with two suspects as they work on a case that has multiple victims appearing in the same city.

"The BAU believes two unsubs may be operating at the same time, when victims killed in two drastically different ways are discovered in the same city. Also, the team grapples with keeping Reid safe in prison," the episode listing on The Futon Critic reads.

Aside from the case, the team will try to find ways to keep Reid safe in prison as more bad things will come his way, according to executive producer Erica Messer.

Messer shared with TVLine that "There are a lot of internal and external factors that are yet to come in that storyline. So hang on tight."

The showrunner added that they're still enjoying this big arc of Reid on the show. "To take our most vulnerable hero and put him in the last place you'd ever want him to be has I think got people talking, which is great. We want that," said Messer.

Reid's arc will end on the current season's finale episode, where Morgan has been confirmed to return as a guest star.

Variety reports that not only is Morgan visiting the BAU, he will also bring a lead that will help the team finally catch up to Mr. Scratch. Morgan may have left the team back in "Criminal Minds" season 11, but he will be a savior to Reid once he helps BAU capture Mr. Scratch and free them all from his terror.

"Criminal Minds" season 12 airs every Wednesday night at 9 p.m. EDT on CBS.