We're guessing this news has Colbert in better spirits than Thursday night, when he bid an emotional farewell to his former boss Jon Stewart on Stewart's last episode of The Daily Show.
Colbert announced the news himself on Twitter Friday, quipping that Clooney - who was one of David Letterman's final Late Show guests in the spring - might not yet be aware that he's scheduled to appear on The Late Show once again next month.
The Late Show with Stephen Colbert premieres Tuesday, Sept. 8 on CBS. Will you watch?
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