George Clooney, Jessica Alba, Clive Owen, Bono, Ewan McGregor, Idris Elba, Joe Jonas, Kristin Davis, Rob Lowe, Justin Long, Colin Farrell and Evan Rachel Wood have all united in a new PSA to fight a cause: the "F" word.

But, it might not be the "F" word you're thinking of. The PSA is for the ONE campaign, and it's against famine. "Famine is the real obscenity," says Bono in the vid.

Watch above!