"Halo 3" begins where Halo 2 left off. The player once again plays as Master Chief as he falls towards Earth. He crashes in Kenya near the city of Mombasa. He is found by a squad of marines led by sergeant Avery Johnson, the commander from Halo and Halo 2. The player and the marines fight their way through invading Covenant force to a human outpost. Here they find human forces making a last attempt to stop the Covenant from activating a portal they found buried in the Kenyan desert. They are unsuccessful however, and the Covenant open the portal to the Ark, where they will be able to fire the Halos and destroy the galaxy. 