Halo: a large ring shaped space habitat created by a long lost species. The Covenant: an almost invincible alien species hell-bent on the destruction of mankind.

Following a mass retreat from a Covenant attack, the human ship "Pillar of Autumn" finds itself crash-landed on a mysterious ring called Halo. Following the crash of the ship, the marines on board and scattered across the alien habitat, surrounded by the menacing Covenant and are slowly being hunted down and destroyed. Unbeknownst to the Covenant, one of the survivors of the ship isn't just a normal marine. He is the Master Chief, the sole survivor from a super soldier project. With advanced senses, inhuman strength, reflexes and futuristic battle armor, he is more then a match against most Covenant forces. Finding himself almost completely on his own, Master Chief seeks to fulfill his mission: learn the Covenants weakness and destroy them. Along the way he will learn secrets not meant for human minds as he makes his way to the core of Halo and discovers its true purposes...