Working round the clock, contract negotiations and how the route's really decided: Celebrity Race Across the World secrets revealed

Celebrity Race Across the World has returned for a third season, taking viewers on a thrilling adventure on one of the most diverse and visually stunning routes yet.

Four famous faces and their loved ones are headed across the Caribbean and Pacific coast of Central America, but behind the scenic backdrops and very, very long journeys, there is a whole other world of planning thats takes place to produce what viewers tune in to from home.

While audiences watch the pairs navigate unfamiliar countries, surrounded by a language they don't speak, the production team either on the ground or back home in the UK are tracking their every move and ensuring their safety all without interfering with the storylines taking place.

So, just how does it all work? Well, during an in-depth Q&A ahead of the season premiere, series producer Phil Lewis and embed producer and director Lewis Price detailed the elements that goes into filming a beast of a programme, which some viewers may not realise.

In his role as series producer, Lewis explained he is in charge of "overseeing the casting, overseeing the routes, overseeing health and safety, overseeing the edit".

He told RadioTimes.com and other press: "We get an overview of the whole series and making sure that everything comes together. That's really it. Along with it there's many of us, looking after the whole series and make sure that everything comes together."

Across the three Celebrity Race Across the World seasons, the cast and crew have travelled from Morocco to Norway and Brazil and Chile – now, it's Mexico to Colombia.

On choosing the route, Lewis added: "We've got our regular series and we've got the celebrity series, and we're always looking for a route that will take somewhere around 32 days.

"So a journey that will take that length of time, as well as something that will take in different landscapes, different cultures, that will really get us to go on a physical journey through mountains, through deserts to the seas, through the jungle, making sure that it is a route that has diversity, and that the series has an arc, but also that every episode has an identity."

Prior to the celebrities being sent on the adventure, there is a team who trial out the route themselves, all with zero knowledge of where they're going, ensuring they have the same experiences as the pairs would.

Lewis explained: "So they go on the route with security and [a] medic, and also with someone from production who goes along and basically [works] on all of the logistics that we need to know in order for them to do that route, and what they spend on that route gives us an idea of what budget we should give to the contributors on the race as well, which they then obviously also have, and they can top that up along the way.

"So we try and work it out to make sure that it's tight, but not so tight that they can't enjoy themselves, but not so generous that it's easy. So it' a difficult calculation."

• If you're planning a trip abroad, read our financial expert's advice on what to consider before going on holiday

While on paper it sounds like an amazing trip, when you factor in a group of eight people along with crew, there are "many moving parts" to think about.

"Giving everyone an adventure that you cannot buy, like even for these guys [cast] who sometimes probably do quite a lot of travel, even this is not something that they would ever be able to do," Lewis explained.

"It's just an adventure you could not buy. And the main hurdle, is making [sure] that it's turning into the adventure of a lifetime, whilst also balancing this is not an easy place to travel through at all."

Lewis continued: "A lot of areas of the world, we just have one road the whole way through, but picking somewhere like this, there's many different ways that you can choose to travel through it, and also making sure that it's safe.

"We want to keep making sure that it's safe, while also feeling completely raw. [There are] things that we put in place to make sure that the journey stays authentic whilst also [making sure] nothing's actually going to happen to anyone."

In order to ensure everyone remains safe, there is a team on location with the celebrities and their loved ones, but also another team in London who work round the clock.

"The race never stops."

One man on the ground was Price, who took on the role of embed producer as well as "managing a team".

He told RadioTimes.com and other press: "One of the things that I enjoy about the role on race is that you really are managing a team, looking out for everyone there, making sure that you're getting all the things that you need to produce these scenes. It's an absolute team effort."

And while some may think the crew get to sleep in a fancy hotel in between non-filming scenes, that couldn't be further from the truth, as Price added: "But I really do think that the team is really the makeup of those two [Harleymoon and Roman Kemp] and the producer/director. That's the three of us, the people doing the sleeping on the floor, going on the busses. My role does exactly what they do all the time."

While following alongside the teams on their journey, Price is also letting the team back in London know each of their moves.

Lewis noted: "I think I must get about 2000 WhatsApp [messages] every day explaining what they're doing, where they are, what decisions they're making, so that we can follow the story of what's going on, to make sure that, just like any production, to make sure that any thread is started is finished. Stories have beginning, middles and ends.

"So we're keeping an eye on the story arc, and that involves us getting a lot of WhatsApps from the team on the ground."

On hand is also a multi-skilled agent, who does security and operates as a medic should anything happen to someone in the team.

"So every time anyone gets on a bus, stays in a hotel, crosses the road, there's someone out there looking after their safety, they're walking through dodgy parts of route, just keeping an eye looking around them," Lewis told RadioTimes.com and other press.

"And then on top of that, we've got a researcher and a fixer. The fixer is someone who speaks the local language, will be running regular release forms of everyone getting location releases... The researchers often [will] communicate with the producer/director, saying they'll be in the support vehicle. They'll travel ahead of the bus. So then someone is there to pick up them getting off the bus."

So far, the celebrities and their loved ones have made it to their first checkpoint. But who will make it to the second checkpoint first and who will fall behind?

Celebrity Race Across the World continues on BBC One and iPlayer on Thursday 13th November at 8pm.

Add Celebrity Race Across the World to your watchlist on the Radio Times: What to Watch app – download now for daily TV recommendations, features and more.

Check out more of our Entertainment coverage or visit our TV Guide and Streaming Guide to find out what's on. For more TV recommendations and reviews, listen to The Radio Times Podcast.