Publisher's Synopsis
The Keepers of the One Freedom, a fanatical Covenant splinter group, have found an ancient Forerunner installation known as the Ark. Led by an infamous Brute named Castor, the Keepers intend to activate Halo. The Ferrets, composed of Office of Naval Intelligence operative Veta Lopis and her young team of Spartan-IIIs, have infiltrated the Keepers to assassinate Castor. Now there's no choice or fallback plan-either the Ferrets stop the Keepers or the galaxy faces an extinction-level event.
