I wrote Sixty-Six Metres over the course of several years, initially stopping after 7 chapters and putting it down for eighteen months while I was working on something else. But it actually started back in 2011 when I had a short story called ‘No Diving’ published online. It takes place in a Welsh quarry called Dorothea, where the bottom is at just over a hundred metres. It’s a dive site that has claimed a few lives, and the story was about a man who had lost his buddy there, and blames himself, so he goes there to commit suicide (to find out whether he does or does not, read the story). You can read it here.

A colleague at work happened to read it and then called me into his office. ‘Do you need to talk about it?’ he asked, evidently believing it was autobiographical. I laughed, saying it was just a story. ‘Sure,’ he said. ‘Anyway, if you need to talk about it, my door is always open.’ I left, thinking, okay, I may have something here.

I began the novel a year later after a back operation which meant I couldn’t dive for about a year. I was really missing it. So I got out my laptop and started the novel. Seven chapters contain underwater scenes. Several of them may appear realistic, because they are based on some of my diving experiences, e.g.

• I blacked out on a dive in Norway at a dive below 50 metres while carrying out a rescue
• I dived the Scilly Isles, and almost got trapped inside a wreck when some kind soul untied the line my buddy and I had clamped to the outside.
• I dived to 76 metres on air, in Sipidan, looking for (and finding) hammerheads (please do not try this)
• I have over 600 dives under my weight belt, and used to be an instructor

Of course there are some things I haven’t done, like being chased by Navy SEALs armed with spear guns, or trying to enter a ditched helicopter in the Thames while its blades are slowing down. Well, not yet, anyway. Some things are better left to fiction.

The story grew, and evolved from an adventure into a thriller. I got pretty involved with the characters, especially the bad ones. Danton was based on someone scary I used to know, and Lazarus came out of nowhere, but I knew he had to stay. The protagonist is Nadia, closely followed by Jake, the BSAC instructor from the original short story. But it is Nadia’s book, and about her unwillingness to kill, even when she is being hunted by stone cold assassins above and below water.

The other reason I wrote it is that there are so few diving thrillers, and yet the underwater world is so exotic and dangerous. So I tried to capture it. Here’s an early scene from the book (which you can pre-order here), in which a night dive to fifty metres in a Norwegian fjord begins to go seriously wrong…

Excerpt from 66 Metres

The cold hit the nape of Jake’s neck as he rolled backwards holding mask and regulator in place with one hand, torch in the other. Chill water seeped into his hood and gloves. A single droplet defeated his dry suit neck seal and ran down his spine as he righted himself. Finning to the back of the boat, he shone his torch onto his left hand to give Andreas the ‘OK’ signal. In that brief moment he caught the concerned look on Andreas’ face while he lowered the green nightlight into the water to help them find the boat later.

            Jake turned to the others, giving them time to get adjusted. Their torches, dangling from lanyards attached to their wrists, shone downwards, cones illuminating the depths below, sharp halogen light diffusing into shadows. A few silver fish scurried away from the searchlight beams, unwilling to be lit up as tonight’s main course for larger fish. Beneath them the abyss of the fjord sucked downwards. Jake knew the lure of the deep only too well. He lifted his mouth out of the water.

“Fin to the wall. We need a frame of reference as we descend, it’ll help avoid narcosis setting in.”

Jan Erik and Bjorn turned and finned towards the shore. Jake put his head underwater again and shone the beam down until it caught the green, orange and red fauna of the underwater cliff face. He lifted up his head. “This’ll do.”  He angled his torch upwards, still underwater, just enough so he could see their faces clearly, the water refracting the light through the thin layer of glacier run-off hovering near the surface, turning their faces a ghostly green. He searched their eyes. Anticipation had taken over concern. Good. Jan Erik grinned behind his mouthpiece, and Bjorn’s eyes adopted the look usually reserved for sharking blondes at discos.

They were both hungry for this, like he’d been ten years ago when he first dived this deep. The adrenaline rush caught him, too. This is why I dive. He replaced his regulator, gave them the ‘OK’, then the thumb-down signal. They returned both signals, and the trio slipped below the surface.

            Jake dumped air out of his stab jacket and sank backwards, breathing out a little through his nose into his mask to prevent redeye, and watched them do the same. He pinched his nose between forefinger and thumb and equalised the pressure his ears. At six metres he gave them another OK signal, and they returned it. He did his trademark reverse pirouette and dove down head first, arms folded in front so he could see both dive computers, equalising his ears every five metres. Like free-falling, like flying, like surfing, like – diving. All his problems, petty concerns, worries, and unsatisfied desires, condensed into the trail of bubbles behind him, cascading up to the real world where they belonged. He didn’t fin, and every ten metres he jetted a little more air into his stab jacket, compensating for the rising water pressure.

Bjorn shot down in front of him, finning hard. In Jake’s headlight Bjorn looked like a fireball. Clearly he wanted to be first. Jake turned to Jan Erik to stop him from following suit, shaking a flat hand horizontally. Jan Erik rolled his eyes inside his mask.

Jake looked down again but could only see the glow of his light below in a stream of rising bubbles growing larger as they ascended. Bjorn had disappeared. Dammit! Fatality scenarios swirled into his mind. Blocking them off, he followed the stream of Bjorn’s bubbles, and checked his computer. He dolphin-kicked once to arrive faster, but not so fast as to trigger nitrogen narcosis. Out of the grey the cliff-face appeared again, now a seventy degree slope, and there was Bjorn, propped on it with his fins, steady as a rock. Jake sighed through his mouthpiece, and relaxed.

Jake realised he hadn’t been breathing much, and took three slow breaths. As he neared Bjorn he checked his own air gauge: two hundred bar, which was plenty. He and Jan Erik touched the silt with their fins, a couple of metres from Bjorn. Jake checked both his computers. Fifty metres. Exactly. He took a few more measured breaths. He didn’t bother to look around – it seemed to be mainly silt anyway – he just wanted to get them back up to safer depth. He signalled to Jan Erik ‘OK’, then ‘Up’. Jan Erik pretended to wipe a tear from his mask with a gloved finger – he wanted to stay longer. Jake shook his head, and Jan Erik nodded, returning the ‘Up’ signal. Jake turned to Bjorn, who was still balanced on the tail edge of his fins, staring down into the abyss. Jake gave him the ‘OK’ signal, then Jan Erik’s torchlight lit up Bjorn’s eyes. They were bloodshot, glazed, half-closed, as if he was drunk. Nitrogen narcosis. Shit. At the same time that Jake reached out for him, Bjorn gave the ‘Down’ signal, and did a pretty good impression of Jake’s reverse pirouette, and dove deeper into the fjord.

Jake’s fingers just missed Bjorn’s trailing fin and he watched, unbelieving, as Bjorn spirited downwards. In the two seconds that followed, he calculated the odds of catching Bjorn before they went too deep, and whether he should focus on stopping a single fatality turning into a three-diver fatality, then traded that risk against trying to explain to Vibeke and the authorities how he’d stood by and done nothing while watching Bjorn plunge to his death. He flicked his wrist to Jan Erik, gave the ‘Down’ signal and dolphin-kicked hard after Bjorn.

Jake finned fast down the escarpment, exhaling steadily. Depth and time were their enemies. The faster he caught Bjorn, the better. One of his computers, the Aladdin, beeped an alarm. Sixty metres. The rising partial pressure of oxygen would begin killing them soon. Breathing hard, with Jan Erik close behind, Jake raced for Bjorn’s red fins. The second computer, the Suunto, beeped. At last he grabbed one fin and then a leg, and yanked Bjorn around to face him. Both of them were still sinking. They bumped into the sludge-covered escarpment like two drunken men falling down a hill in slow motion. Jake had to let go of his torch. It spun around wildly, strobing like a disco light as he gripped Bjorn’s harness with one hand and inflated his stab jacket full of air with the other. Bjorn’s eyes were nearly closed. Nitrogen narcosis had taken him elsewhere. Jake checked his second computer, the Suunto – the Aladdin had stopped working – sixty-eight metres. His fins found purchase on the slope. He flexed his knees and with both hands shoved Bjorn’s body upwards.

Jan Erik arrived.

Jake could hear his own heart pounding. But there was another, stranger, pulsing white noise, getting louder. The beginnings of oxygen poisoning. He pointed to his inflate button, and he and Jan Erik both pumped air into their jackets. Jake had just given the ‘Up’ signal when Jan Erik’s eyes went wide, seeing something behind Jake. He turned just in time to see a snowstorm of descending silt they must have kicked up whilst chasing Bjorn. The next second it enveloped them like thick soup, and suddenly he couldn’t even see his outstretched hand. He reached out for Jan Erik but he was already gone, hopefully upwards. The white noise was now a din in Jake’s head. He knew what it meant. He was about to black-out. Then he would sink, and then it would all be over.

He finned hard, worked his thighs almost into cramp. He had to get up above fifty. Once he was moving upwards, the air in his jacket would carry on expanding and propel him to the surface. If he blacked out and didn’t wake up till he reached the surface, it would be a nasty decompression incident, but that was preferable to the alternative. It grew more difficult to concentrate. The porridge-like silt meant he could barely read the Suunto, even when he held it right in front of his mask.

He suddenly didn’t know which way was up, or where his torch was. All around him, a sea of clay and bubbling blackness. White noise roared in his ears. Then he remembered – follow the bubbles. Watching their direction in front of his face, he righted himself, kicking hard. Jake felt himself lifting. He dared to hope, and read the Suunto, counting down the metres. Fifty-nine, fifty-eight… He was going to make it. His eyes watered inside his mask. The crushing noise pressed inside his skull. Concentrate! Fifty-three … fifty-two … fifty-one … fifty-two … fifty-three… No!That wasn’t possible! How the hell could he be going down? Numbness crept over him. Unable to fin anymore. His legs not responding. Fuck. Not like this! Seconds, seconds… Then he remembered. He reached down to his right side and cracked open his emergency cylinder. It blasted air into his jacket, squeezed it around his chest and shoulders like an airbag. The white noise whirled like a tornado in his head.

He lost consciousness.

66 Metres comes out 25th August