Overview: Jeremy Clarkson, Richard Hammond and James May hit Donington in three stripped out track cars - the KTM X-Bow, the Morgan Three Wheeler and the Caterham R500. Back at the Top Gear airfield, Jeremy recreates the battle of Britain in an insane aero-engined Bentley and a flame spitting retro BMW. Blur bassist and professional cheese maker Alex James is the star in the Reasonably Priced Car.