The BBC's hit adventure show Race Across the World is back on our screens with a brand new series, introducing a fresh set of five duos going head to head in an epic 15,000-kilometre race across several countries for a chance to win a huge cash prize.
As the series continues and the competition heats up, here's your ultimate guide to the show, including the contestant line-up, the rules, the route, and the famous face who narrates the episodes.
Meet the Race Across the World series 4 contestants
As with the previous seasons, the show sees five duos from different walks of life navigate their epic journey across the world.
Among this year's contestants are two mother and daughter duos: snowboard instructor Brydie and cleaner Sharon, and teacher Eugenie and trainee clinical scientist Isabel.
Also taking part in the race are 20-year-old best friends, Alfie and Owen; married couple, Stephen and Viv, and brother and sister, Betty and James.
Race Across the World series 4 route and cash prize
This time, the contestants will cover Eastern Asia, starting in northernmost Japan. From there, they'll cross an impressive six seas and eight borders before reaching the finish line in Lombok, an island in West Nusa Tenggara province in Indonesia.
During their journey, they'll skirt the path of the "volcanic ring of fire", which is "the most geologically unstable region on the planet", according to the synopsis, and contains 75 per cent of all active volcanoes on Earth.
The first team to arrive at the final checkpoint will walk away with a whopping cash prize of £20,000.
Race Across the World series 4 rules
Each team will begin their journey in Japan with a tight budget of £1,329. From there, they'll have to get creative when it comes to their travel, hopping on buses, trains, and even hitching a ride with strangers.
The usual rules apply for series four, meaning no smartphones, access to the internet or bank cards, and no plane journeys.
Who narrates Race Across the World?
If you recognise the voice that narrates the show, that's because it belongs to esteemed Scottish actor John Hannah, who is known for his roles in Four Weddings and a Funeral, Sliding Doors and The Mummy trilogy.
John has narrated all seasons of the show, including its celebrity spin-off.
Race Across the World continues on Wednesdays at 9pm on BBC One and BBC iPlayer.