Season 21
In the first episode of Season 21, Jeremy Clarkson, Richard Hammond and James May are in a nostalgic mood as they set out to prove that the hot hatchbacks of their youth were better than their modern equivalents.
With Clarkson in a Volkswagen Golf GTI, Hammond in a Vauxhall Nova SRi and May in a Ford Fiesta XR2i, the trio set out on a road trip, encountering a series of challenges along the way including a tricky hill climb course and an unusual visit to the supermarket.
Their journey ends at an old army training ground in Wales where the three presenters and their ageing cars must face the explosive power of the heavily armed and heavily moustachioed Top Gear Police Department.
Also in this episode, star of BBC Two comedy W1A Hugh Bonneville is out on the track testing his driving skills as the star in the Reasonably Priced Car.
Format
The show often features the following segments, amongst others:
Races
The show has featured a number of races where Jeremy Clarkson races a car against other forms of transport, usually involving Richard Hammond and James May taking the same journey by any combinations of plane, train, ferry or bus.
Reviews
Top Gear normally reviews one new car, or group of cars, each week. It's became hugely influential with motor manufacturers, since a critical word from the Top Gear team could have a severely negative effect on sales.
The Top Gear reports are not based on facts or figures, but the opinions of the presenters. Group tests normally involve the three presenters debating the merits and weaknesses of each car.
Star in a Reasonably-Priced Car
In each programme, a celebrity is interviewed by Jeremy Clarkson, and focuses usually on car-related topics and often on cars owned by the celebs themselves.
The guest is whisked off to the Top Gear race track where he/she tries to get the fastest lap time in a Chevrolet.
The fastest lap time is held by The Stig, and guests who have attempted to beat his time have included Simon Cowell, Jamie Oliver and Sanjeev Bhaskar.
Power Laps
In the Power Laps segment, The Stig completes a lap around the Top Gear test track to determine the performance of various cars. The car tested is usually the car that's been reviewed in that episode, but occasionally it can be a car from a previous episode.
The Cool Wall
The Cool Wall is a board where Jeremy Clarkson and Richard Hammond decide which cars are cool, and which aren't, and has nothing to do with how good or bad a car is. The categories are Sub Zero, Cool, Uncool and Seriously Uncool.
Initially, part of that "coolness" factor rested on the extent to which the presenters believed each car would impress English actress Kristin Scott Thomas.
BBC newsreader Fiona Bruce replaced Kristin as their notional judge, after Kristin stated in an interview that she owned a Honda, which was deemed to be "Uncool".
The Stig
The identity of Top Gear's test driver is a secret. Usually. He never speaks nor removes his helmet on camera.
The Stig has also appeared on some of Jeremy Clarkson's motoring specials, such as Heaven and Hell and The Good, The Bad and The Ugly, as well as on the BBC's Whizz Whizz Bang Bang, a showwhich constructs children's inventions.
The Stig's name derives from presenter Jeremy Clarkson's days at Repton School, where, according to Clarkson, new students were always called Stig.
The original black-suited Stig was Perry McCarthy, a former Formula 1 British racing driver who appeared in the 2002 and 2003 shows. However, after revealing his identity in an autobiography, he was replaced in Season 3 with a new, white-suited Stig.
In the hiatus following Season 15, racing driver Ben Collins was revealed to be the Stig in a court battle over Collins' impending autobiography, titled The Man in the White Suit.
In Season 16, which debuted in December 2010, Collins was replaced by a second White Stig, whose identity has so far remained secret.