1Part 1
It’s peacetime in the Gulf of Mexico, so why is the USS Pennsylvania running weapons drills?
2Part 2
A man’s dead. Something’s going on. Something bad.
3Part 3
Penetrate the skull. It’s the only way to stop them.
4Part 4
Advance quickly. Stick together. Do not fire unless you absolutely must.
5Part 5
Riley does what needs doing.
6Part 6
Riley and the remaining USS survivors have one mission: Survive.