In front of a packed house of adoring travel enthusiasts, Reeve recounted some of the highlights of his epic trip, which took in all the extremes of the different countries.

“It’s a journey about so much more than what’s under the waves,” Reeve said. “It’s about the lives of the people who live around it. Journalistically, it’s fascinating. It’s been my most extreme journey, in that it takes in beautiful islands, as well as a wa zone in Mogadishu.”

Reeve also stumbled into a drug den in the townships around Cape Town, an episode that threatened to end badly for the BBC crew. “We went from sunshine and blues skies outside to a very dark, depraved scene,” Reeve said. “I thought, ‘We’ve gone too far here, we’ve over-reached.’ There were these guys sitting around in a drug den, doing crack, with a handgun on the side. For some reason they let us in and let us film but eventually decided they wanted to be paid and wanted our cameras. We made our excuses and left.”

Reeve’s journey to procuring one of the most envied jobs around has been an unconventional one. “I don’t come from a travelling family. I didn’t go to Eton,” Reeve said. “I had never been on a plane until I started working. When I was about 18, I went for a job as a white van driver. I was the only applicant and they still turned me down.” Luckily, Reeve then landed a job as a post boy at The Sunday Times and worked his way up in the world of journalism until making his name by writing a book about al-Qaeda, which became a monster hit in the wake of 9/11.

“I became a bit obsessed with it and somebody was mad enough to publish the book,” he said. “Nobody read it and the advances were pathetic but then 9/11 happened and my world changed pretty much overnight.” Nowadays, Reeve finds himself surrounded by a different kind of killer. For the latest series, he got up close and personal with some hungry sharks. “I went diving in this shark-filled cave, which wasn’t a great way to start my fist underwater dive,” Reeve said. “We’re terrified of these creatures yet we annihilate them, killing millions of them each year and we wanted to explore that.”

That, however, wasn’t the most death-defying of Reeve’s adventures. As part of the series, he found himself in an active conflict zone in Mogadishu. “Mogadishu is a terrifying place. It’s probably the most dangerous place in the world. It’s been at war for decades. There’s war under way every day and we went to the front lines to film it,” Reeve said. “It’s the epicentre of piracy in the western Indian Ocean and you have to address that on land. It affects our trade and we just can’t have failed states, which are a breeding ground for terrorism.”

Of course, Reeve’s travels have not been all trial and tribulation. He has met some inspirational characters on his circuitous journeys. “Another hard aspect is to go and meet these wonderful people,” Reeve said. “You have a short, sometimes intense experience and then you have to say goodbye. the Internet is great for keeping in touch but it’s not the same as seeing them again.”

Reeve recalls the adventures of a Yorkshireman who has created the smallest national park in the world, all on his own tiny island, on which he breeds giant tortoises. “He was a great character. He’s about 104 years old but he loves,” Reeve recalled. “He’s been offered blank cheques from Saudi princes to buy his island but he’s always refused, because he wants it to be a national park for the people of the Seychelles. You’ve got to doff your cap to that.”