I estimated the drop from the bottom of the crevasse to the bottom of the ice tunnel to be thirty feet. Getting down was easy, getting up would be a bitch. The rope wasn’t exactly the kind I had been forced to climb as a teen in gym class, and bundled in extreme weather gear, already exhausted, left me with a nightmarish thought of being stranded in a damn ice tunnel.

Having already cursed my own stupidity back in the sub when we nearly suffocated, I thought was why risk it?

But what about that blue glow?

Triboluminescence is a geological feature of both sphalerite and tremolite. Friction applied to these two minerals actually causes the rocks to glow. It was certainly feasible that the lava tunnel was composed of one or both of these minerals, and that the blue hue was simply caused by the surrounding ice thawing and refreezing, something that had occurred God knows how many times since Vostok had been sealed.

Satisfied with my game of cause and effect, I stood to begin my ascent when the tunnel’s luminosity changed from its blue hue to emerald green.

Dumbfounded, I knelt by the hole and looked inside again. There was no mistaking it, the color had changed.

Lucky bastard… looks like you’re going in.

Removing the rope from my backpack, I tied a grapefruit-sized knot at one end and then wedged the ball inside one of the narrow gaps chiseled into the bottom of the rift. I tested it and the anchor passed. Still hesitant, I tied another eight knots in the rope to give myself something to grip during my climb.

Satisfied I could negotiate the climb, I dropped the line into the ice tunnel. It came up short, but it was a manageable reach.

Grabbing hold of the first knot down, I lowered myself through the hole, climbing down hand over hand like I used to do in tenth-grade phys. ed. So intent was I on not falling that I only took in my surroundings once my spiked boots hit bottom.

The curved tunnel walls dwarfed me. One end ran south in the direction of the bay, the other north toward the mountain.

Two paces to my right was the dead animal.

It was four-legged and gruesome. Half the size of a bear, it had thick reddish-brown grizzly fur but was more dog-like in its appearance, with canine teeth that stretched outside its jowls, a long rodent-like tail, and limbs designed for lumbered sprints through the deep snow.

I confirmed its identity as an Amphicyonid, an extinct species of bear-dog. It was an apex killer during the Miocene. The males were bigger and nastier than the females, and this one must have weighed between two and three hundred pounds.