Jeremy Clarkson pits the Audi RS6 against its rival, the Mercedes E55 AMG, the engineers from Lotus are faced with the challenge of turning an old Lada into a top-notch machine and the Maserati 4200 GT is put through its paces. Plus, a bunch of white van drivers battle it out on the test track, and Michael Gambon is the Star in a Reasonably Priced Car