Kenny Rixton (Nick Wechsler) has already had one strike in his time with Intelligence on Chicago P.D., when Voight (Jason Beghe) caught him in a lie about his associations with underground criminals. But is it possible that he poses an even bigger threat to the unit?

In this exclusive sneak peek from Wednesday's episode, "Seven Indictments," Erin's (Sophia Bush) celebration after passing her requalification exam is short-lived when a cop from another department gives her an ominous warning about Rixton.

"Watch your back," she's told.

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Is this guy harboring a personal grudge towards Rixton, or is there something more sinister behind his advice? Fortunately, by the looks of things Det. Lindsay is quite the sharp shooter — but hopefully she won't get to the point of having to defend herself or one of her colleagues from one of their own.

Check out the video to see more.

Chicago P.D. airs Wednesdays at 10/9c on NBC.