This handsome actor began working professionally before graduating from the Actors Studio Drama School at New School University, missing commencement because he was off filming Wet Hot American Summer. Guest appearances on numerous TV series followed, but it was his supporting role on Alias that introduced him to a wider audience. After leaving the drama in 2003, Cooper played Christine Lahti's much younger love interest on Jack & Bobby and finally landed his first leading role on the short-lived sitcom Kitchen Confidential. In 2006 he took a brief screen hiatus to make his Broadway debut opposite Julia Roberts in Three Days of Rain, though his appearance was overshadowed by Roberts' own, highly publicized debut on the Great White Way. However, more success in moving pictures followed, with starring roles in the fifth season of Nip/Tuck, Yes Man (2008) and the 2009 box-office hit The Hangover, and the plum part of Templeton "Faceman" Peck in the 2010 film adaptation of the 1980s TV series The A-Team.
- Was a member of the Men's Heavyweight Crew team at Georgetown University.
- Worked as a doorman at the Morgan Hotel in New York while getting his MFA in acting at the New School University.
- While at the New School, appeared as an audience member in Sean Penn's episode of Inside the Actors Studio.
- First professional appearance was on Sex and the City in 1999, in the episode "They Shoot Single People, Don't They?"