As Vulture reported in March, Bradley Cooper was only on set for Netflix's Wet Hot American Summer: First Day of Camp for one day. But it appears that David Wain and Michael Showalter got the most out of him, as he shows up often and in an array of outfits in the first full trailer for the series. Also, it seems they plan on making up for it with plenty of new stars playing new characters. Jon Hamm should be able to shoulder at least some of the jawline burden.
Here's the poster: