Jesse Spencer

After weeks of having to deal with the physical and emotional side effects of his near-fatal head trauma, it looks Lt. Casey (Jesse Spencer) is finally getting back to his A-game on Chicago Fire.

In this exclusive sneak peek from Tuesday's new episode (10/9c, NBC), Casey makes a surprising, and possibly life-altering, discovery when he and the team are tasked with trying to locate five victims in a huge apartment building blaze.

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He first finds the severely burned hand of what appears to be one of the victims, but it's what — or should we say who — Casey finds underneath the victim that really gets his attention.

Check out the exclusive clip below:

Chicago Fire airs Tuesdays at 10/9c on NBC.