Overview

In 2552, the alien Covenant attacks a human rebel outpost on the planet Madrigal and massacres all of the inhabitants except for teenage Kwan Ha before the Spartan unit Silver Team intervenes. In a nearby cave system, Master Chief Petty Officer John-117 discovers a Forerunner artifact that responds to his touch, displaying mysterious symbols and unlocking some of his sealed childhood memories. A surviving elite of the covenant witnesses the incident and reports it to the Prophet of Mercy in the Covenant capital of High Charity.

Meanwhile, on the planet Reach, Dr. Catherine Halsey clashes with Admiral Parangosky over her methods for creating a revolutionary new type of AI. After Kwan refuses to cooperate with the UNSC, John is ordered to execute her. John must decide whether to blindly follow his orders.