“Remember what I told you,” he said, “eight meters forward of the starboard rudder and three meters up from the bilge keel.” The divers nodded. “Needless to say, be very careful with that cutting torch.” Again, nods. Rausing made eye contact with both men, but added no smile or well wishes. Then he stepped back and was gone.

“Bottom pressure reached. Transfer to the bell,” the voice from Dive Control echoed in the chamber. The divers collected their helmets and tool belts and walked heavily to a ladder that accessed a hatch in the ceiling of their chamber. Murray climbed awkwardly to the top, spun open the locking wheel, and pushed the hatch open into the diving bell. The bell, which was mated to the chamber, was pressurized to the same ten atmospheres so the hatch opened easily. He ensured all valves were positioned correctly, verified that comms worked and then signaled for McElroy and Aitkens to climb up behind him.

With the divers locked inside, the closet-sized bell was detached from the chamber and swung by a crane until it hung half submerged in the ship’s moon pool, an opening to the sea in the middle of the aft deck of the Depth Charge. As they settled into position for their elevator ride to the bottom, the divers could see some of the crew through a thick Perspex window. They were gathered on the aft deck of the ship silhouetted against the floodlights. Rausing, the tallest, stood with arms folded, a breeze lifting his hair so it wreathed his head in a sort of glowing crown.

Up in the pilothouse, Captain Kovács hovered over a screen with a digital outline of the Depth Charge on it. The ship’s dynamic positioning system whirred on and off, its gimbals and GPS keeping it directly above the exact sea bed coordinates Rausing had specified. All was going to plan. With any luck, they’d be hauling the divers back up in the bell and hoisting their cargo by 0600 and be back in Batticaloa an hour later—nobody the wiser but a few fishermen who’d not thought to ask questions about this gleaming ship that had been in the harbor for the past several weeks.

The hoist whined as it lowered the diving bell through the moon pool into the water. The ship’s floodlights illuminated the bell as it swung gently in the ocean swells. Small fish swarmed the scene, attracted by the light. Slowly, the bell grew smaller and then disappeared from sight, leaving only a bubbling surface. Then the floodlights went dark.

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Burlington House, London. 12 April, 1942