The Dark Crusader. Alistair MacLean

I could see nothing, just a sea surface that was no longer that but a churned and hissing expanse of milky white froth, but my eyes were gradually becoming more adjusted to the darkness and after a minute or so I could clearly make out the smooth black water in the rain-free shelter under the long overhang of the schooner’s stern. Not quite black – it was black flecked with the sparkling iridescence of phosphorus, and it wasn’t long before I traced the area of maximum turbulence that gave rise to the phosphorescence. That was where the screw was – and it was far enough forward to let us drop off over the sternpost without any fear of being sucked into the vortex of the screw.

      Marie went first. She held a water drum in one hand while I lowered her by the other until she was half-submerged in the water. Then I let go. Five seconds later I was in the water myself.

      No one heard us go, no one saw us go. And we didn’t see Fleck and his schooner go. He wasn’t using his steaming lights that night. With the line of business he was in, he’d probably forgotten where the switch was.