The route begins in Cambodia at Siem Reap and then winds downriver to Tonlé Sap lake, before joining the Mekong Delta and sailing into Vietnam. The final port of call is Vung Tau, in south Vietnam.
The presenters are celebrating the great 70s American cars they saw in TV shows, as they road trip around Scotland, creating chaos on the streets of Edinburgh and building a homemade floating bridge across the Hebridean sea.
On a road trip, the trio dish up a hair-raising mountain climb, bomb defusals, propeller powered cars, helicopter stunts and the most thrilling race of their lives before reaching the English Channel for a jaw dropping medieval climax.