“We’re still working on that. I’m downloading the SAT image to the Barracuda’s computer. We highlighted your location and the extraction point as references. As you’ll see, you’re in the southern basin, separated from the northern basin by the Vostok ridge. Somewhere along that rise is the source of the anomaly. We suspect the ridge is part of an impact crater from an asteroid. Celestial impacts often magnetize the geology—that’s how they located the crater in the Gulf of Mexico from the asteroid that killed off the dinosaurs.”

A black-and-white photo pixilated across our computer screens. The image was generated from sensory equipment aboard Onyx and Lacrosse, a series of terrestrial reconnaissance satellites launched into orbit thirty years ago and only recently declassified. The satellites were equipped with synthetic aperture radar and other sophisticated instruments designed to see through cloud cover, ocean, ice, and even soil.

The Onyx satellite had pinpointed our sub by our lasers’ heat signature. The SAR unit had generated the view of Vostok’s topography.

“Captain, we suggest you set a course on heading zero-three-seven. If you average twenty knots, you should reach the extraction point in less than five hours. That will give your team nine hours to collect water samples and explore Vostok before you need to start your ascent.”

“Roger that, Lopez.” Ben brought the sub about until we were pointed on our northeasterly heading, cruising along the surface at twenty knots.

I laid my head back, staring at endless mist as we plowed through perpetual darkness. I could have used my nocturnal glasses, but there was nothing to see. We had just pulled off an incredible engineering feat, gaining access to a lost world preserved beneath fifteen million years of ice, and yet somehow I felt disappointed.

What had I expected? What would have made me happy? Traces of fecal matter from a prehistoric trout? Perhaps a fossil or two?

One thing is for sure: we weren’t about to find anything along the surface.

“Ben, any objections to checking out the bottom?”

“What for?”

“Maybe we can find some fossils.”

Ming raised her head from her computer. “Yes. Very good, Zachary. I wanted to collect silt samples anyway.”

“You two do realize the depths in this basin exceed twenty-five hundred feet?”

“It is a submersible,” I said, winking at Ming. “You’re allowed to get it wet.”

“Suddenly the Sargasso survivor is a daredevil? Okay, Doc. As my tenth-grade English teacher said to me before she popped my cherry, ‘Hold on, kid, I’m goin’ down.’”

I grabbed onto the padded leather support handles as the bow dropped away into a near-vertical descent, the depth gauge’s numbers advancing rapidly.

Four hundred feet…

Seven hundred feet…

“Easy, Captain, there’s no rush.”

“What’s wrong, Doc? I thought you were an adrenaline junkie.”

One thousand feet…

At 1,340 feet I felt the hull groan, the acrylic emergency pod wobbling under the sudden wave of pressure.