[WATCH] 'Criminal Minds' Season 13 Finale Sneak Peek: Is Reid Keeping Secrets from the Team Again?

Criminal Minds ends its 13th season with back-to-back episodes and a finale cliffhanger. First, in episode 21, "Mixed Signals," the team heads to New Mexico to investigate an UnSub who is targeting his victims' temporal lobes.

Then in episode 22, "Believer," when Reid finds former FBI Special Agent Owen Quinn locked inside a storage unit, the BAU questions the credibility of Quinn's bizarre accounts of searching for an UnSub he named "The Strangler."