American actor and producer, known for his portrayal of Lieutenant Lynn “Buck” Compton in the HBO miniseries Band of Brothers (2001), Deputy District Attorney David McNorris on Boomtown (2002–2003), Sean Cahill on Suits, Robert Quarles on Justified, William Parker in Mob City, and Dave Williams on ABC’s Desperate Housewives (2008–2009).
He also appeared in films such as Star Trek: First Contact, Minority Report, Walking Tall, The Guardian, and as Dum Dum Dugan in various Marvel Cinematic Universe films and TV series. He appeared as Damien Darhk on Arrow, and in Legends of Tomorrow. He also plays Malcolm Beck on Yellowstone as well as voicing a variety of comic superheroes and villains in a number of animated films and video games.
Both his parents were born in Ireland. A graduate of Barnstable High, he earned a BFA in acting from Syracuse University in 1988 and trained at the London Academy of Dramatic Arts and Sciences. The actor’s first role was Snoopy in You’re a Good Man, Charlie Brown. He has performed in plays such as As You Like It and A Midsummer Night’s Dream and Waiting for Lefty as well as numerous TV appearances. In 1991, he won a Best Actor Dramalogue Award for Away Alone. He almost gave up acting but his role in Band of Brothers got the attention of Steven Spielberg who cast him in Minority Report (2002).

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