The Pillar of Autumn: Escape to Alpha Halo

The Pillar of Autumn was supposed to carry the Spartan-IIs into Operation RED FLAG. Instead, it leaves Reach carrying the survivors and one of the most important artificial intelligences in human history. This episode examines the final effort to deliver Cortana to Captain Jacob Keyes and get the Autumn off the planet before Covenant forces can destroy or capture it. Noble Team is reduced piece by piece as Carter, Emile, and eventually Noble Six sacrifice themselves to ensure the ship escapes. Captain Keyes follows coordinates associated with Forerunner information rather than making a direct retreat toward Earth, consistent with the need to prevent the Covenant from tracing humanity’s homeworld. Weeks later, the Autumn exits slipspace near an enormous ringworld: Installation 04. Covenant ships are already present. Reach has fallen, RED FLAG is dead, and the surviving warship has carried humanity into a conflict far larger than the one it was fleeing. The escape from Reach becomes the opening movement of the battle for Alpha Halo.