A futuristic war-torn world where the Helghast, a ruthless and technologically advanced enemy faction, threatens the existence of the human Interplanetary Strategic Alliance (ISA). The plot revolves around the ISA's efforts to push back the Helghast forces and liberate the planet of Vekta from their oppressive rule.
The story picks up immediately after the events of the first Killzone game, where the ISA has launched a massive invasion of Helghan, the homeworld of the Helghast. Players assume the role of Sergeant Tomas "Sev" Sevchenko, a skilled soldier in the ISA Special Forces unit known as the "Legion." Sev and his squad are deployed deep into enemy territory with the objective of capturing the Helghast leader, Scolar Visari.