Joaquin Phoenix says he regrets his infamous interview with David Letterman, in which he remained in character for the entire, awkward conversation.

Joaquin Phoenix was the guest of honor on “The Late Show With Stephen Colbert” on Tuesday night, marking his first appearance on the late-night staple since his infamous 2009 interview with Dave Letterman and subsequent on-air apology the next year.

Sixteen years after his previous 'Late Show' appearance, the 50-year-old actor is opening up on his 'uncomfortable' interview with David Letterman.