2526. The Covenant wants to eradicate humanity, and they have the superior technology to do it.

Petty Officer John-117 is leading the Spartans, enhanced super-soldiers, on an attack designed to buy time to gather intelligence and defenses. But some rebels believe an alliance with the Covenant to be its best hope of independence from the Unified Earth Government.

They have a plan to sabotage the UNSC counterattack-and ensure that John-117 and the Spartans never return.