Island of Death

I find myself at the edge of a not too tall cliff. There's a sort of vertical gully in the cliff, apparently where water drains down the cliff and into the ocean. I manage to work my way down the gully and I finally stand on a narrow, rocky beach.
I can see a dock, jutting out into the water, and four expensive looking boats moored to the dock. The boats will probably have a captain and, given the size of the boats, maybe even a crew member or two each. The boats are my best bet to make a little progress here.
I strip down to my undershorts and stow my clothes in a little niche, well above the high water marks. I then swim quietly over to the nearest boat. (I have very little body fat and I tend to swim something like a rock.) I use an old fashioned side stroke and get all of the power I can out of each stroke, to keep me from sinking to the bottom. I make it to the nearest boat and cling to the edge, as I hear voices up on the deck. I wait until the voices seem to indicate a lot of physical effort and then I draw myself smoothly up onto the deck of the ship. I then pause and the voices don't seem to indicate that they noticed my entry. I crawl silently along the deck and into some sort of driver's area. There's a wheel and several gauges. There are also side panels, apparently to block the wind.
One of the guys, who are apparently working on the boat, tells the other guy to get something.
Fetch it boy works his way over to the driver's area. I then help him into the driver's area with my fingers around his throat and my Kung Fu strike into a vital area.
I then pause and see if my dirty work has attracted attention. Apparently not.
After a little time, the guy still working on the boat begins to call for fetch it boy. The guy doing the calling has a low opinion of fetch it boy and his mother (apparently she’s a totally depraved bitch.)
I cough, as if maybe I'm fetch it boy and I'm having some sort of medical problem.
The guy then crawls over to the driver's area and I welcome him in, with enough force to break his neck, killing him.
I then listen for a bit and detect no reaction to the demise of the two boat guys.
There's a door opening into the boat and inside I find a small duffel bag with some electrical meters inside. I empty the bag and then go back out into the driver's area.
I strip the two dead bodies, retaining watches, wallets and even a ring with what appears to be a genuine amethyst stone. I put the booty into the bag and stash the bag. I then strip the corpses and dump them in the water.
There are three more boats to go. The nearest boat has no one on deck. That's bad, because the boat may have an alarm system that would detect me if I try to board.
I put on the shirt and pants from the former boat guy who was the nearest to my size. I then put on a hat he was wearing and I go back into the water. I swim down to the last boat in the line. There's a guy on the deck and he notices someone swimming alongside the boat. I flail a bit and reach silently above me, as if I have fallen overboard and may be drunk. The guy reaches down to grab the drunk's hand and I drag him off the boat and into the water. He makes one quick yelp and then dies as I break his neck. I leave the corpse floating alongside the boat and slowly pull myself up onto the deck of the boat.
A very sleepy voice asks, “Is there something the matter, George?”
I cough as if there's indeed something the matter.
Sleepy voice then emerges from inside the boat. He's about half asleep and unarmed. I cover the short distance to sleepy boy make sure that he'll get back to sleep, forever.
I then use a boat hook to retrieve the first deader from the water. I strip both corpses of valuables and place the valuables in a table cloth, or whatever, and tie the corners into a carry sack. I then strip the corpses, slash them with my knife and dump them into the water, for the fish.