Kill Zone 3

In the climax of Killzone 2, Emperor Scolar Visari is assassinated by ISA forces, triggering a full-scale attack by the Helghan First Army.

Overwhelmed, ISA commanders order a full withdrawal, leaving thousands of their own soldiers to die on Helghan. With the Helghast now driven to seek revenge for Visari's death, the survivors must join forces to find a way home.

After failing to save Visari's life, Sgt. Tomas Sevchenko and Rico Velasquez regroup with Captain Jason Narville outside the imperial palace. With Helghan cruisers preparing to attack their fleet, they are forced to fight their way through the ruins of Pyrrhus, sacrificing most of their remaining armor and manpower in order to reach an extraction point near the edge of the city.

Admiral Orlock, commander of the First Army, is pressured by Jorhan Stahl, the chairman of arms manufacturer Stahl Arms, to either ensure the total destruction of the ISA or turn over control of the army to him.

Meanwhile, Rico receives a transmission from Jammer, a sniper whose platoon has been cut off by the Helghast. Against Narville's orders, he goes to assist them.

The rest of the force attempts to link up with the fleet, but enemy interference leads to several ships being shot down, forcing the remainder to leave without Narville's men.

Six months later, Stahl calls for a vote in the Helghan Imperial Senate to remove Orlock for incompetence, but his request is denied. Furious, Stahl ends his company's cooperation with the First Army and organizes his personal guard to hunt down the ISA, who have set up a base in a remote jungle near one of their destroyed cruisers.

While working to restore the base's communication uplink, the soldiers learn that the UCN has agreed to a ceasefire with the Helghast, effectively abandoning them.

The transmission is intercepted by Stahl's men, who subsequently attack the camp and kill everyone aside from Tomas and Narville, who are taken captive.

Rico and Jammer's platoon, now calling themselves the Raiders, ambush the convoy and free Tomas. They carry out several attacks against Helghan facilities in the area, eventually reaching the main campus of Stahl Arms.

Learning that Stahl plans to publicly execute Narville, Tomas and Rico don Helghast uniforms and rescue him and his fellow prisoners. Accessing the company's mainframe, they discover that Stahl has built his own armada armed with weapons powered by irradiated Petrusite, powerful enough to tear living organisms apart.

Believing himself to be Visari's rightful successor, Stahl intends to win the favor of Helghan by conquering Earth itself.

Fed up with Stahl's arrogance, the senate grants Orlock the title of Autarch, giving him Visari's throne instead. Stahl is ordered to surrender his ships to the First Army's fleet above Helghan so they may be used to attack Earth.

The ISA comes under attack from a massive Helghan assault mech, and though they manage to defeat it, their numbers are reduced to just 60 men. Nevertheless, they deactivate the perimeter defenses around Pyrrhus's spaceport, allowing them to access the imperial orbit command center.

Aware of Orlock's plans to murder him after securing his weapons, Stahl double-crosses and kills him before launching an attack on the First Army, giving the ISA a desperately needed opening to steal several Helghast transports.

Stahl orders his flagship to warp to Earth, but Tomas manages to destroy its warp coil, causing the ship to plummet towards Helghan's surface.

A direct nuclear strike ordered by Narville obliterates the vessel, causing it to drop its Petrusite arsenal on Helghan.

The resulting fallout destroys what remains of the Helghast, leading Tomas to comment on how many innocent lives must have perished as a result of their actions. With the war over, the last of the ISA returns to Vekta.

Around the same time, two Helghast soldiers recover an escape pod from Stahl's ship. Though the occupant's identity is not revealed, it is implied that Stahl is still alive, which is confirmed by the sequel

Characters of Killzone3

Andrew Bowen as Sergeant Thomas 'Sev' Sevchenko. The main protagonist, Sev, along with Rico and Narville, lead the resistance against the Helghans.

Charles Everett as Sergeant Ricardo 'Rico' Velasquez. Rico, along with Sev and Narville, helps lead the resistance against the Helghans and forms his own squad with Jammer, the Raiders, while stranded for six months on Helghan after being separated from Sev and the other ISA forces.

James Remar as Captain Jason Narville. Captain of the stranded ISA forces on Helghan.
Brian Cox as Scolar Visari. The dead Autarch of Helghan.

Though absent in the game, he is seen and speaks during the intro (as in every game) in a scene which occurred before the nuclear explosion during Killzone 2.

Ray Winstone as Admiral Orlock. One of the two main antagonist, Orlock is the hot-tempered and strict commander in chief of the Helghan military and soon becomes its autarch.

Malcolm McDowell as Jorhan Brimve Stahl. One of the two main antagonists, Stahl is the CEO of Stahl Arms, a weapons company, he seeks to become Helghans new autarch as he believes Orlock is a nothing more than a miserable excuse of an officer. He also holds little respect for the Helghan military as he looks at the soldiers as "fat", "lazy" and "careless"
oafs among other qualities.

La'Myia Good as Jammer. A resourceful female ISA soldier.

Mac Brandt as Kowalski. An ISA soldier who helps Sev through the Kaznan Jungle.

Mark Engelhardt as Hooper. A rookie ISA soldier who helps in take down Stahls cruiser before the nuke is dropped on it.

Rob Brownstein as Bradshaw