After perplexing fans recently by announcing he was quitting acting to become a hip-hop artist, the 34-year-old Joaquin Phoenix appeared on the David Letterman Show Wednesday night to promote his last film, “Two Lovers,” but gave only stammering one-word answers. Joaquin Phoenix’s bizarre appearance had the audience laughing as the actor let Letterman’s pointed, mocking questions go unanswered.

Letterman starts off by grilling him about his beard, and then asks, "Can you tell us about your days with the Unabomber?" 

Phoenix shifted in his chair and fiddled with his scraggly beard during the seven minute interview. He never took off his dark sunglasses. At one point, he pulled a wad of chewing gum from his mouth and stuck it to the host’s desk.

This follows a May spot on “The Tonight Show With Jay Leno” in which Phoenix was so distracted Leno requested that he ''be here in person'' next time. Phoenix's camp had no comment, but Late Show exec producer Maria Pope replies: ''He's been on three times now. The first couple of times we thought there was a gas leak in the greenroom. Now we've determined, no, that's just Joaquin.''

Many are now questioning if all this is just an elaborate hoax on media and fans alike. However, Phoenix assures it is no joke: "There's not a hoax," Phoenix said. "Might I be ridiculous? Might my career in music be laughable? Yeah, that's possible, but that's certainly not my intention."

In case you’ve missed this one, the star of "Walk the Line" and "Gladiator" announced last fall that he was quitting acting to pursue a career in music, saying that "Two Lovers" would be his final turn in front of movie cameras. News of the unusual declaration is threatening to eclipse the film itself, seriously testing the long-standing adage that there's no such thing as bad publicity.