Almost the whole cast and crew of 'Mad Men' participated in a music video sing along to 'Bye Bye Birdie' at the season three wrap party, and it's on YouTube (via NYMag).
It was apparently a tribute to show creator Matthew Weiner and features drunken participants, lots of red Christina Hendricks wigs (but no Hendricks) and a gum-smacking, texting Elisabeth Moss.
It also has a blooper reel at the end, and Jon Hamm looking adorable. WATCH:
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