Jeremy Clarkson tests Volvo's claim that the new S60 R can challenge the BMW M3 before attempting to drive a Vauxhall Signum from the back seat using little more than string and garden equipment. James May investigates the futuristic, hydrogen-powered GM Hy-Wire concept, while Richard Hammond takes the extraordinary tilting Vandenbrink Carver for a spin and tries to decide whether it's a car, a motorcycle, or something in between. Elsewhere, Graeme Le Saux champions the Audi Quattro as the greatest car ever made, and Patrick Stewart is the Star in a Reasonably Priced Car.