I’ve always been a bit confused about Malaysia. It’s not that it’s a very confusing place, it’s just that geographically, as a country, I’d never really got my head round it. There’s the “peninsula” bit that borders Thailand to the south ... except for Singapore, at the bottom, which isn’t part of Malaysia, but used to be. Then there’s another bit on the same island as Borneo, which isn’t Borneo, it’s Malaysia ... except for Brunei. That’s different. Then there are loads of little islands dotted around the place that are Malaysian. I was going to one of those on this trip. But let’s begin at the beginning.

I flew into Kuala Lumpur, or KL, as it’s known locally. You should never call it Kuala Lumpur – that’s apparently totally uncool. To be honest, a couple of hours in KL is plenty. It’s pretty much nonstop shopping malls (Malaysians LOVE to shop), but one look at the melting pot of a population filling the shops does help to explain Malaysia’s broken geography.

The whole place is a hotchpotch of cultures – mingling with Malays are Indian, Chinese, Scottish, every kind of expat under the sun. For the record, the most impressive mall was under the Twin Towers – the most famous landmark in KL. They used to be the world’s tallest buildings until those pesky Taiwanese went and built something taller and ruined it for everyone.

I was killing time in KL before heading off to an island called Tioman. Sounds exotic, huh? Well, it is. In the 1950s, it was used as the paradise island of Bali Hai in the film South Pacific. In the 1970s, Time magazine called Tioman one of the world’s 10 most beautiful islands. Then, Tioman was riding high. Since those heady days, things have got quieter. A lot quieter.

Paradoxically, unlike most “paradise islands”, which devotees dread being discovered, Tioman seemed to have had her big moment and then faded away. This sounded perfect for me: I was coming for the diving, which I’d heard was magnificent. The news, when I tried to organise a rental car online, that the island actually didn’t have any roads was very welcome. This was going to be a proper escape.

Maybe I’d finally found an island destination that wasn’t chockablock with honeymooners (what is that urge to go to an island on your honeymoon all about?). Maybe it would be stuffed with bong-smoking hippies? Not likely. You don’t see many hippies in Malaysia. This is predominantly to do with the draconian drug laws. Anyone planning to get stoned in a hammock or trip the light fantastic at a full-moon party has come to the wrong place. That’s no bad thing as far as I’m concerned. I’ve had it up to here with dull, annoyingly young and nauseatingly smug drug tourists. Mind you, I went through KL rather than Singapore because my hair’s getting a little shaggy and I wasn’t sure whether the authorities there still stamped SHIT in your passport (Suspected Hippie in Transit).

I flew to the “capital”, Tekek, in a tiny twin-prop run by the island’s only five-star resort, Berjaya. The plane didn’t work at first, and then, when we finally took off, something went wrong and we were forced to return to KL in a more than slightly nervous state. When I finally landed on the island the next morning, I was simply happy to be alive, and the extraordinary physical beauty of the island didn’t hit me until a little later. Huge, tall ridges of thick rainforest sliding gently down onto virgin, white, sandy beaches bordered by an azure sea ... this would most definitely do.

THE MAIN ATTRACTION in Tekek is the aforementioned five-star resort, which seemed to me a fairly soulless place. Having experienced its air service, I decided not to stay there. This was the best move I made all trip, as I ended up at a little gem called Swiss Cottage, at the far end of the town. It is right next to the dive shop I had booked in with and I had a sweet little beach hut with a panoramic view of the bay. When not diving, I’d sit in the shade of huge pine trees that framed a long, pristine beach stretching off into a hazy distant sunset. It was heaven.

Most people leave Tekek immediately and take a boat from the jetty to a hotel or village along the island. Tioman is only 13 miles long, and the interior is almost entirely covered in deep, impenetrable rainforest. Most “chav-packers” tend to head straight for the main hang-out of Salang. I took a boat over there one day. Not to put too fine a point on it – it’s a hole. A half-finished commerce centre scars the beachfront, and it only gets worse as you follow a cement footpath past ever-tackier restaurants and stores. I couldn’t wait to get back to Tekek.

At first sight, Tekek doesn’t have much to offer. Tioman is a duty-free island and sells alcohol, unlike the mostly dry mainland. There are several small, unattractive shops flogging cheap booze and cigarettes (I particularly recommend Lite Ups) for as little as 10p a packet. This can make the place look tacky, but dig deeper and it’s an extremely unspoilt, mellow place.

Most nights, I went to a little restaurant up the road called Sarng, where I became addicted to a particularly fine mutton curry. Mutton is so underused in the UK, and I’m a huge fan of the stuff. It’s perfect for stews and curries. Every night I’d munch my way through a huge bowl while watching the fascinating little fat man who ran the place. He’d always be sitting, shirtless and with a big smile, behind his desk, endlessly counting piles of money and smoking cartons of Lite Ups. He was the spitting image of one of those laughing buddhas that you see in tacky markets in Bangkok. It was Laughing Buddha who informed my friend Kaj, a couple of days after I’d left the island, that the “mutton” they served was, in fact, goat. Ah well, it was delicious. Goat is so underused in the UK ...

There was also the “satay man”, who made the stuff at home. We’d order a hundred or so sticks between six of us every other afternoon. We’d then go and pick them up in the evening and wolf down the whole lot with lashings of his homemade spicy peanut sauce and bags of fresh cucumber. If I had my way, this particular delicacy would be given its own chat show immediately by the Malaysian television bigwigs. This would be a marked improvement on most Malaysian television, which seemed to consist mainly of imams giving long and rather fierce-looking sermons. It reminded me a little bit of Iranian TV – except that I was watching it in a duty-free shop.

Anyway, on to the reason I was here. The diving was superb – loads of fabulous stuff to see. We mainly dived around a smattering of little islands made of huge perforated boulders, hurled on top of each other in the dim and distant past by some unthinkable great force. I’d squeeze myself through tight caves chasing cuttlefish and turtles the size of cars. One particular “speciality” of the area are nudibranches. These are a weird type of sea slug that comes in all sorts of amazing colours, and many divers collect sightings of them with the intensity of train spotters. I found it difficult to get that excited by them. I’m a fairly amateur diver and I still like Big Things.

One evening, we anchored off the tiny island of Renggis, entirely covered in thick vegetation where fruit bats sleep. We bobbed up and down and watched as a twister of Christmas frigate birds arrived. As they slowly tightened their noose on the island, the first fruit bat made a break for the shore. Within a minute, a vast, dark cloud of bats temporarily hid the last rays of sunset as the Christmas frigates took their place for the night.

The air tattoo over, we slid into the warm sea and floated down to the sea bed, spending a gloriously lazy hour drifting past a huge coral circus performing in our torchlights.

I loved Tioman. Sadly, I’m not the only one. If you’re going to visit, then do it fast. The five-star resort is about to build a huge airport into the sea to attract more visitors. All this despite the presence of an extensive marine park around the island. The damage that this construction will inevitably wreak on its ecosystem will be awful. The good news is that the planes will be bigger and more reliable than the one I arrived on, but, as the hordes descend, and roads and resorts are built to accommodate them, another special part of the world will be gone.

Dom Joly travelled as a guest of Kuoni

Travel details: Kuoni (01306 747008, www.kuoni.co.uk) has a nine-night trip to Malaysia, with seven nights, B&B, at the Berjaya Tioman Beach, Golf and Spa Resort (www.berjayaresorts.com) and two at the Capitol Hotel, in KL, room-only, from £1,082pp, including flights from London with Malaysian Airlines, domestic flights with Berjaya Air and transfers. Or try Best at Travel (0870 709 3071, www.bestattravel.co.uk). For information on diving in Tioman, visit www.tioman-dive-centre.com or www.liquidguru.com .

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