Beginning aboard the Forward Unto Dawn, on which Cortana and Master Chief were stranded after the events of Halo 3, Cortana begins by musing of her seven years of existence and that she has learned a great deal more about the Forerunners than was previously known. The story then shifts to a Forerunner planet before the invasion of the Flood, and then leads up to infection of the planet and it's eventual orbital bombardment.
Começando a bordo do Forward Unto Dawn, em que Cortana e Master Chief ficaram presos após os acontecimentos de Halo 3, Cortana por devaneios tem aprendido muito mais sobre os Forerunners e a origem do grande confronto.
Повествование о вселенной Halo начиная от 100 тыс лет до нашей эры и до 2553 года...
Mientras el Jefe Maestro y Cortana siguen varados en el espacio, esta última decide elaborar un informe sobre la historia de los Forerunners y la Humanidad. "Origins" narra parte de la historia Forerunner.
