Joaquin Phoenix Acts Bizarre On 'Late Show'

Former actor Joaquin Phoenix came out of retirement briefly Wednesday night to promote his new and presumably last movie.

Phoenix's appearance on "The Late Show with David Letterman" was marked by bizarre behavior during the interview, and a decidedly different look from what audiences are used to seeing. Dressed in a black suit, the Oscar-nominated "Walk the Line" and "Gladiator" actor sported long hair, a full beard and sunglasses.

"It's been three years since the last time you were on the show and I will say right off the top here, you look different than what I remember," Letterman cracked. "You got a nice beard going."

Phoenix apparently didn't like Letterman's remarks about his chin growth and responded, "I'm OK with it -- you don't have to make me feel weird about it."

Phoenix appeared withdrawn and reserved during much of the interview and mostly responded with short answers.

When Letterman asked Phoenix to set up the clip for the movie he was promoting, "Two Lovers" with Gwyneth Paltrow, the actor appeared lost and looked back at the late-night host's band leader, Paul Shaffer and said, "Are you (bleeping) kidding? Are you kidding, with the maniacal laughter? I don't know what the clip is."

The actor later appeared with Paltrow at the film's New York premiere.

The actor created a buzz in Hollywood in October when he announced that he was quitting movies for a music career. Phoenix mentioned his music briefly to Letterman, and said that he was concentrating on doing hip-hop.

"I'd love to come on the show and perform," Phoenix said -- although Letterman responded to the idea with sarcasm.

To end the interview, Letterman said to Phoenix, "Joaquin, I'm sorry you couldn't be here tonight."

Phoenix responded with a smile, "He's funny, he's funny. He's a funny dude."

Some bloggers are suggesting that Phoenix's behavior is all part of an elaborate hoax. TMZ.com speculated that he is "no doubt he's shooting a mockumentary with (friend and brother-in-law) Casey Affleck ... pretending he's quitting acting to become a rap star" and "showing how the media will fall for it."