Theroux is also a talented film writer. In 2012 he co-wrote 'Rock of Ages' for Warner Bros. Directed by Adam Shankman, the film stars Tom Cruise, Alec Baldwin, and Catherine Zeta-Jones. Theroux also penned 'Iron Man 2' for Paramount Pictures and Marvel Studios. The film was directed by Jon Favreau and stars Robert Downey, Jr., Gwyneth Paltrow, Mickey Rourke, and Scarlett Johansson. Prior to 'Iron Man 2,' Theroux teamed up with Ben Stiller to pen and executive produce DreamWorks' 'Tropic Thunder,' starring Stiller, Robert Downey Jr., Jack Black, Nick Nolte, and Matthew McConaughey.
Theroux's acting credits include David Lynch's 'Inland Empire,' Zoe Cassavetes' 'Broken English,' Michael Mann's 'Miami Vice,' Ben Stiller's smash hit comedy 'Zoolander,' David Gordon Green's 'Your Highness,' Mary Harron's 'American Psycho,' David Wain's 'The Ten,' 'The Baxter,' 'Strangers with Candy,' 'Charlie's Angels: Full Throttle,' 'Duplex,' 'I Shot Andy Warhol,' Greg Berlanti's romantic comedy, 'The Broken Hearts Club,' and 'Romy and Michele's High School Reunion.'
Theroux made his directorial debut with 'Dedication,' which premiered at the 2006 Sundance Film Festival and was released by The Weinstein Co. Developed by Theroux from the script by David Brombert, the romantic comedy stars Billy Crudup, Mandy Moore, Tom Wilkinson and Bob Balaban.
On television, Theroux portrayed John Hancock in HBO's award winning mini-series 'John Adams' alongside Paul Giamiatti, Laura Linney, and Tom Wilkinson. He had a guest starring arc opposite Amy Poehler in 'Parks and Recreation' and was a recurring character on HBO's acclaimed series 'Six Feet Under.' Theroux has also appeared on 'Alias,' 'Sex and the City,' 'Spin City' and 'Ally McBeal.'
Theroux began his acting career in New York theater, starring opposite Philip Seymour Hoffman in 'Shopping and F*cking,' followed by 'Three Sisters" with Calista Flockhart, Billy Crudup, Jeanne Tripplehorn and Lili Taylor. He last starred in Frank McGuiness' 'Observe the Sons of Ulster Marching Towards the Somme,' an examination of the individual and collective desire to honor one's beliefs and country. For his performance, Theroux was honored with a Lucille Lortel Award, as well as the Boston Critics Award for Best Male Actor.