Race Across the World pair sneak ahead of the competition in first look

But in order to reach it, like the previous episode's checkpoints, they must use their wits and speed in order to head through the Maritimes, Canada's three smallest provinces – New Brunswick, Prince Edward Island, and Nova Scotia.

Because of the time they reached the sixth checkpoint, best friends Tricia and Cathie set off last, 20 minutes behind everybody else. But even so, it appears that they've somehow managed to surpass them all and get the last remaining tickets for the coach needed to get to Liverpool.

In the clip, we see the pair arrive at the bus station where they're told there's a bus that afternoon at 2pm, and they're then told that they're "going to be the last persons". They realise that they've got the last tickets for the bus just as we see how Ladi and Monique, and then Claudia and Kevin are told by the same ticket provider that they've missed out on today's bus.

Instead, they have to buy bus tickets for the next day, which, understandably, nobody is happy about. Even so, Tricia and Cathie remain pleased at the fact that they've somehow managed to pass the others.

While they've secured the last bus tickets out of town to New Brunswick, will the other teams manage to find an alternative way to get ahead of them? We'll have to wait and see.

Watch the clip above.

The official synopsis for tonight's episode reads: "Just two more legs remain. After starting the race 41 days ago on Canada’s Pacific coast, the teams now have the Atlantic within their reach – lapping the shores of the seventh checkpoint at the seaside town of Liverpool, Nova Scotia.

"To reach it, they head through the Maritimes, Canada's three smallest provinces – New Brunswick, Prince Edward Island and Nova Scotia. To keep their lead, Zainib and Mobeen aim to test the local hospitality to the limit, but a trip to catch a naturally occurring phenomenon – on a sinking raft on the highest tide in the world – may derail all their hard work.

"Claudia and her dad Kevin are running on fumes and, with costly taxis out of the question, need emergency surgery to mend their ailing budget. But a bad start, where they end up spending money to go backwards, makes their challenge even more difficult."

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It continues: "After faltering in the last leg and dropping into last place, the stress of the race is beginning to get to best friends Tricia and Cathie. Can they mend their differences and get themselves back into a strong position in time for the final push to the finish line?

"A string of failed attempts to hitchhike shines a light on the obstacles Monique and Ladi face. The only team remaining to have not won a leg, it’s now or never if they are going to turn themselves into genuine contenders."

With only a couple of legs of the race left to go, it really is all to play for and this episode will see them battling fog, torrential rain and the spotty Canadian transport system to gain an advantage.

While many fans will be sad to hear that the series is drawing to a close soon after each week's tense episodes, it has been confirmed that a celebrity version of Race Across the World will air later this year.

Speaking about the new series announcement, BBC commissioning editor Michael Jochnowitz said: "Well, we filmed it at the end of last year and it's in the edit. It's looking incredible.

"It's probably more of a traditional race in terms of number of countries that they're going to travel through. It will be out later this year."

Race Across the World season 3 continues on BBC One and BBC iPlayer on Wednesday 3rd May at 9pm.

Previous season are available to stream now on BBC iPlayer. Check out more of our Entertainment coverage or visit our TV Guide and Streaming Guide to find out what's on.

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