Dean Winters

On the Law & Order: SVU finale, Capt. Cragen will defend an old colleague who hasn't been on the show in more than a decade.

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Season 1 star Dean Winters returns on Wednesday's episode as Det. Brian Cassidy, now an undercover cop who is involved in the team's latest case. "It looks like he could be a little shady, and it's up to Cragen to say, 'I know Brian and he's a good cop,'" Dann Florek tells TVGuide.com. Unfortunately, Det. Amaro (Danny Pino) doesn't quite believe him. "It's contentious with Amaro," Pino says. "Dean's character is not as affable as Amaro would like."

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In the video below, Florek and Pino talk more about the Season 13 finale. Plus: Ice-T shares a message for any fan who threatened to stop watching the show after Christopher Meloni's departure. (Hint: He doesn't like you.)

Watch our exclusive behind-the-scenes video from Dean Winters' return:

The Law & Order: SVU finale airs on Wednesday at 10/9c on NBC.