The Mekong Delta. A vast portion that stretches over 40,500 square kilometers (15,600 square miles), covering a large part of southwestern Vietnam.

This is where the Mekong River empties into the South China Sea, after running through China, Myanmar, Laos, Thailand and Cambodia, and where The Grand Tour filmed the Season 4 opening.

Warning: Spoiler Alert!

For the episode that will air on December 13, on Amazon Prime, which is dubbed ‘Seamen’, Jeremy Clarkson, James May and Richard Hammond, together with a big crew, dropped the usual wheels for boats. Sailing may be Jezza’s thing, as the other two prefer riding motorcycles whenever they don’t drive cars, but the challenge was more than all of them could chew at different points, as the official trailer right below shows.

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The co-presenters had to cross the Mekong Delta “without any issues”, something easier said than done – or, as Clarkson would put it, “what could possibly go wrong?” Well, a lot of things, actually, so in the lengthy adventure, they can be seen smashing their boats into things, getting lost, encountering technical issues, becoming stranded and getting a few cold showers – all to the amusement of viewers.

If you’ve made it to this part, then you obviously do not care about spoilers, so you may want to head on down and check out the teaser video, too.