As a veteran of not one but two terrifying journeys along the World's Most Dangerous Roads, Rhod Gilbert is the perfect host for this white-knuckle joyride through some of the highlights from the past two series. But it's not just a road trip down a very bumpy memory lane: Rhod also introduces plenty of previously unseen footage, deleted scenes and hilarious out-takes rescued from the cutting room floor.

For Alex, who missed out on the backpacking escapades his friends enjoyed in their twenties, it's a chance to make up for lost time, while for self-confessed ‘pathetic driver' Ellie it's a chance to stretch herself with a brand new challenge.

Taking the wheel on the first morning, a confident Alex sets out from the town of Bandung – but by the end of the day, a combination of steep mountain tracks and horn-honking locals have left his nerves in shreds. He won't drive again for nearly two days.

As their quest gathers pace, our intrepid duo brave terrifying roads, perilous river crossings, and high-altitude plateaus where sulphurous springs spew forth noxious fumes that leave them gagging. But it's the climax of their adventure that packs the biggest punch. Alex and Ellie's final challenge sees them tackle the ascent of Indonesia's most active volcano, Mount Merapi – a dangerous undertaking, with a truly terrifying sting in the tail.

The little-known former Soviet Bloc country is a place of remote steppes and mammoth mountain ranges, which can only be crossed via perilously narrow rocky tracks. Starting from the capital, Bishkek, it doesn't take long for the road to head steeply upwards – but it's soon clear the biggest threat comes from the homicidal overtaking manoeuvres of the local drivers, who display a cavalier disregard for blind bends and oncoming lorries. While Jake squirms in the passenger seat, Jack decides to join in the fun, only adding to Jake's terror.

Over the coming days, Jack and Jake face multiple obstacles, from horrifyingly narrow roads with only a sheer drop for company, to muddy tracks rendered almost undriveable by rainstorms. But for Jake in particular, the driving is only half the challenge. For a man who lives life to a strict routine, being starved of home comforts (including the morning shower he hasn't missed for 20 years) is a real ordeal. And things hit rock bottom when he's struck down by a mystery illness that threatens to cut short their entire trip.