I almost feel sorry for Jasper. The sheer panic in his voice shows that he’s terrified. There he was, relaxing on his boat, listening to some music on his headphones, when suddenly he’s locked in and—so far as he knows—kidnapped.

Alfie, though? Alfie is as cool as can be. It’s as if he’s got one thing to do, and nothing—nothing—is going to stop him. He’s steering the boat, jaw tight, eyes screwed up, peering through the gathering rain.

I don’t know how fast we’re going. Boat speeds are measured in knots, and I’ve no idea how big a knot is. Looking at the water rushing past us, though, we’re going at least as fast as a car driving through a town. The wind is deafening and the sail is a huge white curve, filled completely. We’re in luck with the wind: it’s coming straight off the land and taking the yacht directly to the island. We’ll be there in a matter of minutes.

“Hello? Hello? This is Delta Foxtrot One Niner. Delta Foxtrot…”

It’s Jasper on the radio. He’s screaming for help.

“Hello—do you read me?…Is that Dave? Dave! Are you in the lookout? It’s Jasper Hooke. My boat’s been stolen, looks like we’re heading straight for the island, and I’m on board, trapped below. I’ve been kidnapped, Dave. Call out the Coast Guard. Call the police! Call anyone! Over.”

Dave’s voice crackles back.

“Coast Guard just returning from an abortive mission, Jasper. Hoax call, we reckon. Blimey—is that you out there? You’ll win the America’s Cup goin’ at that pace, Hookey. Get ’em to turn round—it’s not safe. Over.”

“I can’t, you idiot, I’m…I’m kidnapped. They’re not gonna turn round just because I ask politely! Call the Coast Guard station; tell them to divert the rescue boat to the island and intercept us! Over!”

“Who’s kidnapped you, Jasper?”

“I don’t know, Dave! I’m locked in, I can’t see them.”

“They may be armed, Hookey.”

“For heaven’s sake, Dave! They may also have a man-eating tiger with them for all I know. Just do something before this thing capsizes with me in it. Over and out!”

There are footsteps on the stairs leading to the door, followed by a loud banging as he tries the door again.

“Let me out! You’re gonna be in so much trouble. This is piracy. You’ll hang for this!”

Then it goes quiet. It’s an uneasy silence, as if the silence itself is planning something. The steely water is rushing past the hull, and by now the rain is coming at us almost horizontally, but the sail is taking all of the wind and there’s a sweet spot in the wheelhouse where everything is dead quiet.

I look across at Alfie and he has this grin spreading across his face—the grin of someone in the grip of certainty—and it’s awesome! I know then, at that precise moment, that—no matter what happens with this boat, or with Jasper, or even with me—Alfie will succeed. Despite my terror of everything that’s happening about me, I reach across Alfie and flick the switch that I’d seen Jasper flick that day he took me and Dad out.

Instantly the air is filled with unearthly music: the centuries-old Gregorian chants. For a few seconds—maybe as long as half a minute—we sail in glorious peace, abandoning ourselves to the wind, to the sea, to our fate.

Then I see it, coming through the crack in the doorway: a small knife, sawing at the rope that’s holding the door shut. In a matter of seconds, it will have cut through.

At the same time, bouncing across the waves toward us at a heck of a speed is the Coast Guard rescue inflatable, the yellow-clad figures inside getting bigger by the second.

As is the island.

We’re heading straight for it. The sea is so wild by now that the rocks aren’t always visible, but when the swell drops, there they are: huge black stones like whale backs curving out of the surface, and in seconds we’ll be smashed up on them.