One of Britain’s most influential hard rock bands sets out on a tour across the United States to promote their latest album, Smell the Glove. Joining Spinal Tap on the road is Marty DiBergi, a filmmaker and devoted fan determined to shoot a documentary along the way. Rob Reiner’s feature debut is a defining mockumentary, anchored in the quirks of the greatest bands of the twentieth century and the oversized egos of their members.