What's the part at 02:50 a parody of?

[GameMaster]

It has to be from a musical...

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[Jason1]

I happened to watch this on TV the other night, halarious. I cant believe some of the people they got to do that!

[Swan]

Can't see it but I'm assuming its the Ben Affleck sexing one.



Amusing video;)

[Fox 6]

Harrison really didnt look too "into it" during the sing a long.