John Slattery Makes a 'Mad Men' Confession About Jon Hamm and Spills on Directing Him (Exclusive)

John Slattery chats with ET about reuniting with Jon Hamm for 'Maggie Moore(s),' out in theaters on June 16. John reveals if it was a risk to cast his former 'Mad Men' co-star in the crime movie. He also dishes on directing Tina Fey and how it was Jon's idea to hire her. Plus, John shares if he'd ever appear on 'And Just Like That.'