Casey didn't really think he could keep his affair with the new Chief's ex on the DL, did he?

In this exclusive sneak peek from Tuesday's new episode of Chicago Fire (10/9c, NBC), Interim Chief Pat Pridgen (Matthew Del Negro) wastes no time telling Casey (Jesse Spencer) that he knows Casey was sleeping with his ex-wife, before she became his ex-wife.

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"How do you want to split it up, Casey?" Chief Pridgen tells Casey. "What's that, Chief?" Casey innocently asks. "The alimony payments," the Chief tersely replies.

Awkward! So who spilled the beans on Casey's extracurricular activities? Find out in this exclusive video:

Chicago Fire airs Tuesdays at 10/9c on NBC. Anyone else missing Chief Boden right about now?