Starting just after the ending of the original Killzone, and revisiting many of the events from the Killzone trilogy, the game puts players in the rugged combat boots of a mercenary named Arran Danner. Danner, a former UCA soldier, has no qualms about taking on paid contracts from the ISA, as well as the Helghast.

Starting just after the ending of the original Killzone, and revisiting many of the events from the Killzone trilogy, the game puts players in the rugged combat boots of a mercenary named Arran Danner. Danner, a former UCA soldier, has no qualms about taking on paid contracts from the ISA, as well as the Helghast.