Joaquin Phoenix, David Letterman

Few can forget Joaquin Phoenix's bizarre appearance on Late Show with David Letterman in February. Now the actor is returning for round 2 on Wednesday, Sept. 22.

While promoting his last dramatic film, Two Lovers, the 35-year-old actor appeared on Letterman in 2009 looking disheveled and behaving strangely. Despite Letterman's best efforts to get Phoenix talking -- asking him about his co-stars, his beard, and his "days with the Unabomber" -- Phoenix gave terse, one-word answers.

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At the time, Phoenix had recently announced his decision to take time off from acting to focus on a music career as a rap star. "I think you're taking a little time off tonight," Letterman joked during the interview, which attracted more than 8 million views online.

Still, Phoenix offered to come back and perform on the Late Show. Letterman laughed, but promised to keep him in the rolodex.

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Phoenix is currently promoting his new documentary, I'm Still Here.

Watch the interview here:

CBS will also re-air Phoenix's full interview on Thursday, Sept. 16.