December 1944. South China Sea.

USS Bergall slices through black water, her crew executing a standard mine-laying operation off the coast of French Indochina when it picks up an unusual transmission. Powerful, military-grade, and too strong to ignore. Lieutenant Commander John Hyde abandons his post and rushes to his submarine’s periscope.

Through the narrow lens, Hyde scans the horizon. The darkness reveals nothing at first, then a shadow materializes against the night sky. A massive Japanese warship the US Navy has been hunting for months.

Hyde has seconds to assess the situation. The Bergall sits in waters too shallow to dive; yet, Hyde orders the forward tubes prepared. Six torpedoes tear across the sea toward the target. Two explosions illuminate the night, revealing a vessel engulfed in flames.

The Japanese ship somehow appears to split in two. But now instead of sinking, both halves are pointing right at the Bergall to attack…