Jack had a starring role in Neighborhood Watch. He has also appeared in the Twilight series, playing Royce King II.
Other credits include Ben-Hur in Ben-Hur, Flavius in Spartacus, Factory Girl, Shrooms, Miss Austen Regrets, The Garden of Eden, Boogie Woogie, Shrink, Eastwick, the West End production of Strangers on a Train, Outlander, Salome, Not Fade Away, Two Jacks, Night Train to Lisbon, and American Hustle.
He also appears in the HBO series Boardwalk Empire playing the role of Richard Harrow.
He also played the part of narrator on avant-garde musician John Zorn's album A Vision in Blakelight, an homage to William Blake.