Revealing mistake: Watch the opening sequence of this episode very carefully - Clarkson, May and Hammond are not in Downing Street (they are on a set that stands on the BBC backlot) and library footage of the Prime Minister is cleverly edited in to make it look as if they were there at the same time. Even taking into account the fact that the Prime Minister's security service would never allow such an intrusion onto Downing Street, the line up of the shots does not quite match - our three intrepid heroes should be visible in shot when the Prime Minister is shown exiting number 10, but they are nowhere to be seen. It is all sleight of hand and clever editing, but detectable if you watch carefully enough.
Character mistake: Both Jeremy Clarkson and his guest Sir Michael Parkinson identify "The Four Yorkshiremen" sketch - about four Yorkshiremen trying to outdo each other with their complaints about life - as a Monty Python sketch. It isn't. It is from "At Last The 1948 Show", presented by David Frost, and was first performed by Tim Brooke-Taylor, John Cleese, Graham Chapman and Marty Feldman, although Monty Python have often performed it.
Patagonia Special: Part 1 - S21-E8
Revealing mistake: On their boat trip to Tierra del Fuego there are a number of sweeping overhead shots of the ferry upon which Clarkson, Hammond and May are travelling. Their very distinctive cars are not on deck. There is nowhere on the only deck that they could be under cover. The footage of the ferry was filmed on a different voyage.
Continuity mistake: During the police car challenge, Richard Hammond is taking his homemade police car around the track on a timed lap (with extra points for flamboyant driving). As he rounds the Hammerhead corner, the makeshift stinger (that's a spike strip for the colonials) on the front of his car breaks off and is left behind. He then drives through a stack of boxes, getting one caught on the remains of the stinger mounting. As he approaches the second-to-last corner, the box has gone and the stinger is now back on the front of the car. In the final shot as his car limps across the finish line, the stinger is once again missing and the box has returned. Clearly footage from a different lap was substituted in. (00:51:10)
Continuity mistake: In the final show of season twelve, the Vietnam Challenge, when Jeremy Clarkson borrows James May's bike to try to pass his practical driving test, throughout the test, it can be seen that May's "Darcey Bussell" statue is not on the bike. He then conversed with May and Richard Hammond, still seated astride the bike and "Darcey" is still not present. As Clarkson gets off the bike and lets it drop, still in mid-conversation with no breaks, the statue is suddenly strapped tightly onto the luggage rack, just in time to break on impact. (00:47:00)
Continuity mistake: When The Stig first stops for fuel, during the Caterham challenge, Richard is shown looking at the map of his progress and you can see that he is somewhere between London and Oxford, even though we saw him pass this point earlier.
Continuity mistake: During "the 24 hour race". Hammond and Clarkson are helping to put extra 'racing car bits' to their car. In the one of the shots of Jeremy and the fuel tank, you can see the sponsor stickers they stuck on. But the audience hasn't seen them being stuck on yet. In shots after, there are no stickers; until we see them being added.
Continuity mistake: Near the end of "Star in a Reasonably-Priced Car," Jeremy Clarkson is telling Alastair Campbell his time. When we see the wall of lap times, there are eight stickers. Clarkson tells Campbell his time and, when the camera changes, applies the sticker second from the top. The camera changes back and the wall only has the same eight stickers as before.
Continuity mistake: When Jeremy is going up in the lift, near the end of the Bugatti Veyron vs plane race, the screen behind him shows that he is going up through floors 25, 26 and 27, in one shot. But, seconds later, he stops on the 23rd floor for directions, when he had been going up and was already beyond that.
Continuity mistake: During the Amphibious car challenge the second time, there are shots when crossing the channel of Jeremy not having the fishing rods on the Hilux, yet when he arrives, he does.
Revealing mistake: Jeremy Clarkson remarks early on in the episode (during the journey to Da Lat) that he would rather "hop to Hanoi." Later in the episode, the trio make a mistake whilst purchasing their train tickets and accidentally travel to Hanoi rather than Ha Long City. The comment made suggests that the plan was to travel to Hanoi all along and the "mistake" was scripted.
Continuity mistake: When the team are trying to build a Caterham, Jeremy puts the seats in the wrong way round. But, when they knock the car off the blocks, the seats have gone. Then Jeremy is later shown removing them.
Audio problem: When Jeremy and James are playing I spy, just as Jeremy says "If you say S, I'm going to kill you!" there is a shot from outside the car and you can see that his lips aren't moving.
Continuity mistake: At the end of series 13, after Richard uses a cherry picker to stick a cool wall picture out of Jeremy's reach, Jeremy jams the controls and goes to interview Jay Leno. But throughout the interview, the cool wall is visible in the background and the cherry picker has gone. Afterwards, Richard is back in the same place without having had time to move.
Other mistake: When Mattie first gets her kite out, Richard says that they are in the same fjord where Jeremy and James went through the ice. If so, the scenery has changed remarkably in a couple of days. All the blue ice is gone and so are the cliffs, which prevented Jeremy and James driving out. He can't have taken a different route as the fjord is only a mile wide.
Continuity mistake: In this episode filmed in New Zealand, Jeremy races in a blue Toyota Corolla. Later, Jeremy wrecks the blue Toyota and is replaced with a red one (same car, just a different colour). During a scene after the blue car is replaced, Jeremy says "Back on gravel, I wasn't expecting that" if you look carefully at the B pillar from the inside it's blue, from the previous car. The B pillar inside the red car is red.
Continuity mistake: During Jeremy's timed lap in his police car, Richard and James watch him go from the start/finish line. But, when James comments about Jeremy having unbalanced the wheels, they are standing in a completely different part of the track. They then return to the line as Jeremy finishes.
Continuity mistake: In the 17 year old car challenge, Clarkson's car wipe can be seen going, then stopped for a few a shots, then going again. This is when he explains that the wiper is broken and stuck on.
Continuity mistake: During the motorhome race, the little red Toyota has a fold out space sticking out of the roof. But it disappears and reappears in almost every shot right up to the moment it splits off.
Continuity mistake: When James is attempting to outrun The Stig in his van, there is a shot of him along a straight which Jeremy's door is lying in, indicating that he's already passed follow through. The shot then changes to show it from Richard and Jeremy's point of view and James is in the background rounding follow through.
Suggested correction: This isn't something they hide. Behind the scenes interviews make it quite clear that they have a B unit that films additional footage of the areas they travel in. They even take the cars back to get more shots of them on the road, since they can't predict the exact routes that will be taken in order to have camera crews ahead of them in time.
The mistake is perfectly valid. The correction is only providing an excuse as to why the mistake occurs. Most shows/films have a second unit director and crew (the "B unit") solely to film supplemental footage. This does not invalidate the point of the mistake, that "their very distinctive cars are not on deck" where they should be.
Super Grover ★
Since they cut to and from shots of Hammond, May and Clarkson standing on the deck of the boat the implication is clear - the shots are continuous. It is a glaring error.