I also retrieve the small backpack that is holding the rubber-coated utility anchor attached to the braided line, and I stuff my pistol and suppressor in it, along with my knife, a flashlight, and a small red light to use underwater.

While Talyssa watches the approaching yacht, I strip down to my underwear and wrestle into the 7-millimeter wetsuit, pull the hood over my head, and slip on my fins.

She starts to say something to me, maybe to protest again that she has no training to pilot a powerful motorboat on the open sea, alone, at night, but she registers the intense look on my face and realizes I am not a man to be reasoned with right now.

I put the mask on, adjust the snorkel, and sit on the gunwale of the speedboat, facing in. Crossing my legs in front of me, I say, “You’ve got this, and so do I.” Before she can reply, I pinch my nose and put my hand on my mask. I roll backwards off the gunwale, entering the water with the back of my head first, then doing a reverse somersault under the waves before resurfacing.

With my head back above the waterline, I get her to hand me the backpack, and I put it on my chest with the straps over my shoulders.

“Go,” I say. “I’ll call you when it’s done.”

Five minutes later I am bobbing alone in the dark water, making little corrections with my fins as a very mild current tries to pull me offline from the oncoming vessel.

My plan is as simple as it is crazy, but as I told Talyssa, I’ve done something similar before. When the boat comes level with me I will fin as hard as I can towards it, then throw the grappling hook at the metal railings alongside the sea stairs at the rear. I’ll be lashed to the line, and then I’ll use it to pull myself through the yacht’s wake to the stairs.

That’s the plan, anyway. But it will only work if I can get close enough to throw, and if I can get high enough in the water to throw, and if I snag the hook on the rail, and if there isn’t anyone standing right there to stop me.

Easy day, Gentry. You got this.

If there is anyone down on the lower deck by the sea stairs, this plan won’t work at all. I’m not shooting someone from the water and then just climbing on board and fighting it out, as cool as that would be, so this plan of mine is conditional on what I see in a one- or two-second look at the stern, as well as the execution of my throw.

Getting into position will be tough. I can’t be right in front of La Primarosa when it passes or it will either run me down or suck me down. Instead I try to plant myself about fifty feet east of where it will pass.

One thing’s for sure: I’ll only get one chance at this, and failure means those women sail off to Italy or Slovenia or somewhere else in Croatia, while Talyssa and I motor back to shore, miles from town, with no earthly idea what to do next.

But I can’t think about the prospect of failure because La Primarosa is just a few hundred yards away now. I commit myself to my objective, put all my energy and focus into it, and prepare to move.

The freediving fins I’m wearing have more than twice the surface area of regular swim fins, and this, along with decades improving my finning technique, allows me to move like a torpedo through the water. I dive just a few feet, then begin working my legs as hard as I can, and I close on the path of the vessel.

I can’t see anything below the waves without my light, but using it now would tie up a hand I need for something else, so I just have to estimate how far away I am by my speed in the water and the loud humming noise coming from the one-hundred-fifty-foot-long vessel.

I surface, blow out my snorkel, and look up. The bow of the Primarosa is more or less where I’d hoped to find it, fifty feet in front of me to the west. The speed of the vessel up close is frightening, and the white caps of the bow wake along the hull are intimidating, because I’ll be swimming right through that in seconds.

I don’t dive this time, I just lower my head, breathe through my snorkel, and kick like my life depends on it. My heart pumps wildly, thanks to the adrenaline and epinephrine and cortisone from the fear, excitement, exertion, and desperation.

And as I kick, I have the weird presence of mind to realize something in this moment.

I fucking hate to admit it, but I live for this shit.

Just then I feel the wake hit me, knocking me back to the left as the vessel churns the sea, heading to my right.

Six seconds later I arch my back and my head surfaces; I kick as hard as I can while vertical, lifting my upper torso out of the water. The stern of the boat is close enough but already past me, and I realize I should have surfaced a couple seconds earlier for an easier throw.

From my imperfect view I see no one on the lower deck by the sea stairs so, while still kicking to keep my arms above the water and fighting the incredible wake, I swing my right hand over my head, hurling the four-pound metal utility anchor up and over the stern railing. The rubber coating I sprayed on the tongs masks any metal-on-metal noise, and I’m hoping the sound of the engine hides the clunking of the instrument when it hits the deck and again when it catches on the rail.

I quickly wrap my wrist and forearm in the rope and hope like hell that I am yanked along in the water.

I’m violently jerked and towed behind the yacht. I pull myself handover hand up the rope through the foamy wake, using all the strength in my arms, legs, and back to do so. The mask is ripped off my eyes by the force of the water, but it slides down onto my neck and not over my head. I gulp a mouthful of seawater and fight the incredible drag of the small pack on my chest trying to haul me under the surface.

This? This is not the shit I live for.

But I keep pulling, and soon I take a hand off the rope and reach up to the sea stairs, looking for something to grab on to. I’m weakening by the second from exhaustion and the need to suck in a breath of air, impossible in the heavy wake of the megayacht.

A small tie-down is positioned just to the right of the water entry of the sea stairs, and my fingers take it in a death grip. I let go of the rope with my left hand now, wrap it over my clenched right hand, and, like I’m freeclimbing a sheer wall, I pull myself out of the water and onto the lower stairs.

I fight the urge to vomit and to cough up a large volume of the Adriatic Sea and to collapse down onto the deck, because I haven’t cleared the area around me yet. Barely able to function, I pull the suppressed G19, rise onto my knees, and, still with the massive fins on my feet, I scan the rear portion of the lower deck over the top of the stairs.

The area is clear.

I drop back onto the lower stairs, out of view from the deck, and take a few seconds to recover from the exhausting swim. I gag out seawater for a few seconds, and this makes me feel a lot better. Finally, I remove my fins and fold them till they fit in the pack. Taking off my mask and snorkel, I shove these in, as well.

I’m head to toe in a hooded black wetsuit, with black neoprene boots and a black pack on my chest, which I shift around to my back after retrieving my knife from it.