"Law and Order: Special Victims Unit" is the longest-running spin-off in the franchise, and over the past 22 seasons, the series has had plenty of guest stars.

Elizabeth Banks, Hayden Panettiere, Carol Burnett, and Sarah Paulson all played murderers on the crime drama.

Other celebrities who played criminals on the series include Henry Winkler, Robin Williams, and Hilary Duff.

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With 21 successful seasons, so far, "Law and Order: SVU" stands apart as the franchise's longest-running spin-off — in fact, it's already surpassed the 20-season run of the original series.

Throughout its run, "SVU" has featured countless celebrity guest stars, and in some of the series' most memorable episodes, those actors played the villains.

Here are some of the celebrities you probably forgot played criminals on "SVU":