Jon Hamm Jon Hamm

It's appropriate that Jon Hamm's directorial debut — the second episode of Mad Men's fifth season — will air on April Fool's Day, as I hear the Mad cast hammed it up at his expense. When Jon instructed Vincent Kartheiser, who plays Pete, to take three beats before delivering a line, "Vinnie took the note incredibly literally by counting 'One, two, three,'" says John Slattery (Roger).

Later, John plotted his own prank with Elisabeth Moss (Peggy). "Slattery and I had this whole thing planned to prank Jon by talking really, really quietly so he could just barely hear us, and he'd be checking his headphones," says Elisabeth. "But Slattery started laughing and totally chickened out." In his defense, John says, "It was my first scene back in a year, and I think I was drunk... or playing drunk."   

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