When the Janus key has been completed and the UNSC saw a Forerunner outpost that is far away from the Sol system. They sent the Infinity and her fleet along with the Arbiter's Swords of Sanghelios fleet of the Shadow of Intent to investigate. Now what they find leaves them in shock. That there is a planet that is inhabited by Human and Faunas and if threats that lurk in the planet. What will happen to them.