In this first episode, Jeremy attempts to build a car that's even smaller than the famous Peel P50. He then tests it out on the streets of London before putting his concept to the ultimate test of credibility in the fearsome Dragons' Den.

Meanwhile, James is testing the latest Bentley Continental GT Speed by taking it on a rally stage. Plus Richard is at the test track to unleash the sensational new Pagani Huayra hypercar before handing it over to The Stig for the lap of its lifetime. Homeland star Damian Lewis is the star in the Reasonably Priced Car.

The brand new series of the world's most popular car show continues with an epic road trip across the western side of the United States in three front-engined supercars. With Jeremy Clarkson in a Lexus LFA, Richard Hammond driving the new Dodge Viper and James May choosing the latest Aston Martin Vanquish a glorious soundtrack is guaranteed, as are furious arguments about which is best as the trio head from Las Vegas to Los Angeles and on to Palm Springs. Along the way, the three presenters take in racing circuits, airborne attacks and a race against the police before making a break for the Mexican border with a terrifying penalty for the last car to make it. Meanwhile, back in the studio, legendary Fleetwood Mac drummer Mick Fleetwood is the star in the Reasonably Priced Car.

Jeremy Clarkson, Richard Hammond and James May engage in an epic race from Wembley to the San Siro stadium in Milan. Hamstrung by a rule about price, Clarkson maximises his bang-for-buck with a 35,000 pound, 662 horsepower Shelby Mustang GT500, while Hammond and May pin their hopes to the ever-improving pan-European rail network. For the winner, tickets to a top flight football match. For the losers, only the stench of failure and a long trudge home. Plus, Jeremy slithers about the test track in the brand new Toyota GT86 coupe and car-loving singer-songwriter Amy MacDonald is the star in the Reasonably Priced Car.

Jeremy test drives the new Kia Cee'd and also plays an unusual game of rugby involving James Richard goes behind the wheel of the Mastretta MXT, but is concerned about the repercussions of a comment he made in a previous episode about Mexico, the sports car's country of manufacture.

Jeremy and Richard attempt to solve the problems complex cars pose to an ageing population by creating a vehicle for elderly people and putting it to the test in Dorset. James finds out more about with the latest Range Rover in London before pitting the luxurious off-roader against an autonomous military machine in Nevada. James McAvoy is this week's star in a Reasonably Priced Car.

Jeremy, Richard and James travel to Africa on a mission to discover the definitive source of the Nile. They believe that they can do a better job than explorers who claim to have discovered the waterway's starting point by travelling further and faster than previous efforts.

In the second part of the Top Gear special, Jeremy Clarkson, Richard Hammond and James May continue their epic African odyssey.

Having survived insane traffic, lethal mudslides and some distinctly dubious map reading, the trio and their ailing estate cars reach the climax of their quest to find the definitive source of the Nile.