Long before he was Roger Sterling on Mad Men, John Slattery made his acting debut in a far less successful TV series, which was based on the World War II action classic, The Dirty Dozen. It aired on FOX in 1988 and only lasted eleven episodes and I think one of the main reasons it didn’t take off is because this modern version of the Dirty Dozen didn’t feature any major stars. After the likes of Lee Marvin, Charles Bronson, John Cassavetes and Telly Savalas, I don’t think names like Ben Murphy, Glenn Withrow and Barry Cullison really cut it. However, John Slattery was able to break out of the pack and have a pretty successful career afterward, but it’s weird seeing him with dark hair in this clip.