The Divide (2011)

A group of survivors turn Lord of the Flies after a nuclear attack in The Divide (2011). Nuclear missiles have hit Manhattan and some residents manage to hide in basement of their apartment building before the neighborhood comes crashing down. The building's super, Mickey (Michael Biehn), seals the door behind them; he has some supplies on hand, since he's been living in the basement. But as the days wear on, the rations start to run low, and tension over who should lead the group turns into a bloodthirsty power struggle.

Hot off his role as Peter on the TV series Heroes, Milo Ventimiglia simmers as one of the survivors.  While he has bigger worries after the nuclear attack than showing skin, he does brighten up the dreary situation with a scene that shows him in his boxer shorts.  His body shows no signs of nuclear damage and the bulge in his boxers might be just the lifeline you need.