Aston Martin DB4

Ant Anstead follows the car hunters of auction house RM Sotheby's as they search for the world's most expensive cars. An Aston Martin DB4 GT worth £2.5 million is made ready for London auction by taking part in an exclusive classic car rally. In the South of France, two rallying classics, a Peugeot 205 and a Renault 5 Turbo, are hoping to fetch a million dollars each. And a 1958 AC Aceca-Bristol is put up for sale in California.