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Fallon and Leno Tease Audience With Duet

Late Night host Jimmy Fallon took time out from his own busy singing schedule to appear on The Tonight Show last night, teaming up with host Jay Leno for a slightly tweaked, April Fool’s version of “Tonight” from West Side Story.

The duet comes amid the negotiations to crown Fallon heir to The Tonight Show throne after Leno finally retires — whenever that unspecified date may be…