Megaton(2010)

Set in the ruins of the Capital Wasteland, the story follows Lars, a wandering scavenger who arrives in the fragile settlement of Megaton, only to find the town already teetering on the edge of collapse. After a cryptic encounter with a disfigured preacher and an uneasy alliance with a local mercenary, Lars is approached by a stranger offering him caps to detonate the bomb at the town’s center.

Official site