From Verified Handles
Dean Gerard Winters (born July 20, 1964) is an American character actor. He is known for his role as Ryan O'Reily on the HBO prison drama Oz and had roles in TV series Rescue Me, 30 Rock, Sex and the City and Law & Order: Special Victims Unit, as well as portraying "Mayhem" in a series of Allstate Insurance commercials. from Wikipedia
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