During an assault against the Promethean forces following the rise of the Guardians and the emergency slipspace jump of the UNSC Infinity, Matthew, a young SPARTAN-IV, regains the memories he had lost for a while due to amnesia, to learn he has a brother. Matthew will sacrifice everything, his standing among the UNSC, his rank, his safety, to be reunited with the family he never knew he had. Will his sacrifices be in vain? And if he does find his brother, will he find himself up against a danger he has never even imagined? (The story takes place after Halo 5: Guardians)