Dean Winters is an American actor best known for his television roles as the Machiavellian Ryan O'Reilly on Oz (1997-2003), and as Johnny Gavin on Rescue Me, from 2004-2009 (with a guest appearance in the final season).
A native of New York City, Winters spent time growing up in Arizona before graduating with honours from Colorado College.
His television career started in 1995 with a recurring role on the Emmy Award-winning Homicide: Life on the Street, a part that started a long professional relationship with writer and producer Tom Fontana.
From there, Winters went on to guest star on the series NYPD Blue, New York Undercover, Millennium, Sex and the City, Deadline, Third Watch, The Twilight Zone, and CSI: Miami.
Along with recurring roles on Law and Order: Special Victims Unit, he has been a series lead on both Rescue Me and Oz.
In 2006 he landed a recurring role as Dennis Duff on the sitcom 30 Rock and in 2008 began playing terminator Cromartie in the science fiction series Terminator: The Sarah Connor Chronicles, replacing Owain Yeoman in the role after the pilot episode.
On film Winters has been seen in a number of features, including Conspiracy Theory, Undercover Angel, Snipes, Brooklyn Bound and Bristol Boys.