Crystal was a long-time friend of Williams and the pair worked together on the film "Father's Day."
Joining Crystal will be singer Sara Bareilles with a special performance honoring the late actor.
Recently, she dedicated her song "Hercules" to Williams, but no word if that's the song she will sing.
Williams was found dead in his home earlier this month after an apparent suicide.
He was 63-years-old.
Emma Stone is the new leading lady coming to Broadway!
The actress will star as Sally Bowles in the revival of "Cabaret."
She takes over for actress Michelle Williams November 11th.
But her time at Studio 54 is a limited engagement - until February 2015.
Tom Cruise is accepting a new challenge - the wildly popular ALS ice bucket challenge!
He isn't alone...With 'Mission Impossible 5" Chris McQuarrie by his side.
"We don't want to miss the 24-hour deadline so Tom and I are here to take a hit for the team," says McQuarrie.
So the cast and crew of "Mission Impossible 5", make sure the buckets of ice water keep coming.
Cruise says donations will be made to ALS on behalf of every cast and crew member of the film.
(Mary Mueller for CNN's Hollywood Minute)
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