Justin Timberlake's Surprise Performance at Diddy's Miami Party

Justin Timberlake made a surprise appearance at David Grutman’s Story Nightclub in Miami Saturday night.

The party was hosted by Puff Daddy and Justin was watching in the wings, when he got a mic and sang "Holy Grail."

Justin was in Miami for his "Man of the Woods" tour, where he performed earlier in the night at the American Airlines Arena. The tour is doing super well.

We couldn't see his wife, Jessica Biel in the crowd.