Gwyneth Paltrow Isn't Buying Joaquin Phoenix's Hip-Hop Act

'It seems odd,' actress says of her 'Two Lovers' co-star's decision to swap acting for rapping.

Gwyneth Paltrow isn't buying all this Joaquin Phoenix hip-hop hype.

Yes, even despite Phoenix's rather thuggish behavior at a Miami concert on Thursday — when he leapt into the crowd and wailed on a heckler — Paltrow, who stars with Phoenix in the film "Two Lovers," isn't convinced that he's given up his acting career to focus on rapping.

"I'm not a hundred percent sure that that's really going to be the case," she told MTV UK during a promotional junket for the film. "I think that there might be some other explanation or something going on. I'm not quite sure what, but I can't believe that he's really going to quit forever to become a rapper. It seems odd."

And that puts Paltrow squarely in the ever-growing camp of people who suspect that Phoenix's hip-hop career is actually just an elaborate hoax, despite his publicist's assertions to the contrary. But even if she has her doubts, that doesn't mean Paltrow's not paying attention to Phoenix's every move. And she might even be taking a few notes.

"I'd like to take this opportunity to announce that I'm quitting acting to become a rapper," she laughed. "So, I'm going to write 'good-bye' across my knuckles and everything. Do you have a pen?"

While our colleague didn't have a pen handy, he did manage to ask Paltrow — who has sung both onscreen and onstage, and who, along with husband Chris Martin of Coldplay, is close friends with rapper Jay-Z — if she had any advice for Phoenix on his burgeoning hip-hop career. Turns out she did, and it's actually pretty sound: Start building street cred.

"What advice would I give to Joaquin?" she laughed. "Hmm ... maybe to go live in the projects for a few years to get some authenticity, maybe."

Check out everything we've got on "Two Lovers."

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