In the decade since his fiancee was killed, an Army Ranger, Green Beret and Navy SEAL rolled into one (Will Forte) has sworn off fighting crime, preferring instead to rock his mullet as a man of peace. But when his sworn enemy, Dieter Von Cunth, steals a nuclear warhead, only MacGruber and his crack team of experts (Kristen Wiig, Ryan Phillippe) are equal to the task of bringing the villain to justice.