The Big Boffin Burnout

S3 E7: Top Gear looks at the German contribution to the world of motoring. Jeremy Clarkson takes Porsche's stunningly fast Cayenne off-roading at an Army tank-testing range. In Cape Town, South Africa, Richard Hammond gets his hands on Mercedes' fastest road car, the SLR - developed by Formula 1 team McLaren. And James May looks at some of the worst handling cars on the market. And this week's Star in a Reasonably Priced Car is the award-winning comedian-impressionist Rory Bremner.