The captain rotates to the west and focuses on the advancing eye wall. It is as if he is looking out from inside the heart of a tornado. A dark purple wall of clouds—swirling, twisting, igniting every few seconds in bursts of lightning—the storm is a living, raging beast.

‘Conn, sonar, all ships now in position.’

Wilkins pulls himself away from the periscope and readjusts his cap. ‘Very well. Officer of the Deck, put us on the ceiling. Increase speed to sixteen knots.’

‘Aye, sir, surfacing ship. Increasing my speed to sixteen knots.’

‘Conn, sonar, give me two pings down the fleet’s bearings.’

‘Aye, sir, two pings.’

Two thunderous gongs echo across the sea, alerting the other Trident subs, which have fanned out along the eastern eye wall.

‘Weather Net Officer, this is the captain. Begin ejecting MPK gas.’

‘Aye, sir. Ejecting MPK gas.’

Located amidships, standing in pairs like steel redwood trees, are the sub’s twenty-four vertical missile silos, each rising more than three stories. Originally designed to launch sixty-five-ton Trident D-5 II nuclear ballistic missiles, the tubes have been refitted to hold compatibly sized canisters of pressurized cryogenic nitrogen gas mix.

Weather Net Officer Matt Winegar activates the digital clock on his control board, then presses EJECT-1 and EJECT-2.

Exterior hatches pop open along the top of the submarine. Seconds later, a clear stream of gas is forcibly expelled through venturi tubes. As the MPK gas mixes with the low-pressure, high-humidity atmosphere, it expands and crystallizes, forming a thick fog, which is quickly suctioned toward the approaching wall of the cyclone.

Immense waves lift and drop the sub, sending several off-duty sailors scampering to the head.

WNO Winegar tries his best to ignore the building queasiness in his gut as he watches his clock. Each MPK tank release must be timed to feed the storm, too much gas at once, and the storm will choke.

At four minutes a green light flashes, alerting Winegar to release the next two batches of compound.

The storm continues east as it feeds, its western eye sucking the chemical up into its vortex, dispersing it within its cumulus fury.

High overhead, flying back and forth through the supercane’s clouds like steel falcons are ESMA’s Unmanned Cyclone Aerial Labs. These four-foot-long winged darts, known affectionately as UNCLE, traverse the walls of the eye, gathering precious data.

The officers and crew of the Pennsylvania hold on and watch as UNCLE’s data appears on screen.

SUPER-CANE KENNETH: SUSTAINED WINDS: 193 MPH

The hurricane’s winds continue dropping. 182mph … 181mph … 179mph …

‘Conn, Weather Net Officer. All silos flushed, skipper.’

‘Officer of the Deck, take us down. Make your depth one hundred feet.’

‘Aye, sir, taking us down. Making my depth one hundred feet.’

Captain Wilkins stares at UNCLE’s numbers, silently rooting for them to descend faster. From experience he knows the MPK gas must decrease sustained winds below 140 mph for the storm’s feedback cycle to be significantly disrupted.