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.
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.
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.