At two-fifteen in the morning, a heavy metallic clang echoed up through the concrete floor of Room 412.
It was not a normal mechanical noise. It had the deep, hollow resonance of a severed high-pressure line, followed immediately by a violent hiss.
Julian Vance felt the vibration punch straight through the soles of his sneakers. The air pressure in the room plummeted with a sharp pop.
“Julian!” Elena Rostova shouted from the doorway. “What was that sound?”
“The foundation,” Julian said, lunging across the threshold into Room 412. “Something just ruptured directly beneath us.”
“Ruptured how?” Elena asked, running to his side. “The water pipes?”
“The nineteen seventy-four isolation drop-shaft,” Julian said. “The contagion bay schematic from the archives.”
“Explain it fast, Julian!” Elena demanded. “What are we dealing with?”
