*A theory about Halo 5 after viewing trailer is made* Here we go: After Cortana's death, Master Chief goes AWOL. After that he goes out and in his anger, he commits crimes against humanity. The UNSC and ONI then send Jameson Locke and his team to capture John and bring him back to put him on trial. On the way, Locke runs into the Swords of Sanghelios, who aid him in his hunt. But when Thel 'Vadam finds out who Locke is hunting and why, he is skeptical. [Story stuff here] Master Chief and Locke confront each other, and the story can end in two ways. Chief's death or Locke's.