The main entrance to the facility consisted of an enormous tunnel that had been bored into the north side of the mountain. Armed guards stationed at the entrance admitted the troops, who deployed with both speed and purpose. The commander of the assault force, Captain Roger Pyle, led his men through a sprawling underground maze of tunnels, branching off into numerous long galleries lined with large sealed compartments. Steel doors, each nearly thirty feet tall, guarded the vaults and their lethal contents, which were routinely sealed inside solid steel canisters. View ports were installed in each door to allow for direct visual inspections.

Moving swiftly but methodically, the soldiers worked their way through the dimly lit tunnels, checking each vault on the go. The precise location of the captured Philippine egg sac was buried amidst layers of official secrecy, misdirection, redactions, and plausible deniability, defying ready access, but Pyle had reason to believe that it was somewhere in this particular gallery, nearly a thousand feet under the mountain. Given the possibility that a second MUTO might be stirring, it had been decided to conduct an immediate search and inspection of the vaults, pronto.

“Move it!” Pyle urged his men. “On the double!”

One after another, view ports were slid open. Flashlights probed the interiors of the vaults, finding only the expected stores of nuclear waste in their airtight casks. So far everything appeared secure, although they had yet to locate the MUTO egg, hatched or otherwise. Pyle had to wonder what the brass was thinking, storing something like that. He would have blown it to pieces years ago.

Then maybe they might not be in the fix they were in.

Pyle hung back, observing the operation, as yet another view port was opened. Instead of the usual darkness, a blinding white light shone in his face. Blinking, he shielded his eyes from the glare and recoiled along with his men. Instantly on guard, soldiers raised their weapons as their comrades warily unsealed the massive hatch. More light flooded the tunnel as the heavy door swung open, revealing a disturbing sight.

Goddamnit, Pyle thought.

The entire vault had been torn open from the inside. An enormous hole, at least three hundred feet in diameter, gaped at the far end of the cavernous chamber, where what appeared to be a newly dug tunnel climbed all the way up to the surface. The blinding light pouring down from above? That was sunshine, Pyle realized, coming from outside the buried repository.

Yucca Mountain had been breached—from within.