Two best mates, two bikes and over 200 miles of beautiful French landscape. David Baddiel and Hugh Dennis, who've been friends for 40 years, pedal through France while getting up to mischief, exploring stunning local sights and having a good old chat along the way. This time, David's cycling mettle - and his dodgy knee - are put to the test as he and Hugh travel along the Canal du Midi and tackle some of the most challenging parts of the route so far. Along the way, Hugh and David visit an artisanal dye expert who reveals the ancient magic behind turning things blue. At the Seuil de Naurouze, they gatecrash an unusual local fiesta, before dining in Castelnaudary - the cassoulet capital of the world - where Hugh can sample his favourite French dish. This leg of the journey culminates at the beautifully preserved medieval citadel of Carcassonne, where Hugh and David uncover its fascinating history and finally take a breather.