After Reid (Matthew Gray Gubler) was brutal attacked in prison at the end of last week's episode of Criminal Minds, you can bet that the members of the BAU are going to look out for their (pretty) boy more than ever.

On Wednesday's episode, Alvez (Adam Rodriguez) visits Reid's prison pal and former FBI agent Calvin Shaw (Harold Perrineau), ostensibly to muscle him into making sure Reid doesn't become a target again. "Reid will not get hurt in here again," Alvez warns ominously.

But he's also got a trump card that he's willing to play in order to enlist Shaw's help: Alvez knows the real reason Shaw turned himself in for the murder of a CI.

Find out what it is in our exclusive sneak peek.

Criminal Minds airs Wednesdays at 9/8c on CBS.

(Full disclosure: is owned by CBS.)