Cold War

"We are in grave danger from the Communists. Our freedom, our very way of life is at risk."

- President John F. Kennedy

The Cold War was a conflict spanning from after the end of the Second World War in 1947, to the collapse of the Soviet Union in 1991, Call of Duty: Black Ops is the only Call of Duty game to take place during this period so far.

Operation 40
Call of Duty: Black Ops revolves around the Cold War, starting out in the level "Operation 40" during 1961, where the player and his squad (consisting of Joseph Bowman, Frank Woods, and Alex Mason) have orders to assassinate Fidel Castro, with help of Cuban rebels. After killing "Castro" (actually a double), the mission goes wrong and the squad, along with Carlos, have to escape Cuba via plane. Bowman tells the squad they will not have enough time for take-off due to enemy vehicles blocking the runway, but Mason jumps off the plane and destroys the vehicles with a ZPU-4, only to be captured by Nikita Dragovich and sent to Vorkuta.

Baikonur
In Baikonur, Mason and his team (along with Grigori Weaver) are tasked by President Kennedy to sabotage the Soviet space program by destroying the Soyuz 2 rocket before it launches, killing Dragovich, and killing rocket scientists working for the Soviets. During the mission, Weaver gets compromised, and Lev Kravchenko stabs him in the eye with a Karambit Knife. Mason and the team eventually find Weaver and destroy the rocket, and continue the mission. The scientists are killed, but Dragovich is not confirmed as dead.

Khe Sanh
Mason's SOG team (comprised of Woods, Bowman, and Mason, accompanied by Jason Hudson) then go to Khe Sanh, South Vietnam, arriving just before Vietnamese soldiers begin the siege of Khe Sanh and have to defend the city with Marine forces. The American soldiers start to push back the Vietnamese and gain the upper hand against them, and are successful in defending the military base.

Hue City
The team then head out to Hue City, Vietnam to locate a Soviet defector in the MACV compound in the city and retrieve his intel on Nova 6. Mason's team then goes through the compound and locate the intel, then fight to the landing zone with help from air support. The American forces eventually reach the landing zone and escape with the intel, after destroying an enemy ZSU gun emplacement and holding off a Vietnamese counter-attack on the landing zone.

Kowloon City
A CIA team consisting of Jason Hudson and Grigori Weaver are sent to Kowloon City, Hong Kong, to interrogate Dr. Clarke, who had helped Dr. Friedrich Steiner stabilize Nova 6. Spetsnaz forces attack Clarke, Hudson, and Weaver to prevent the CIA from retrieving intel from Clarke. The team moves throughout the buildings in Kowloon City and when they reach a steep and slippery rooftop, Clarke slips and is shot in the head while dangling from the roof. Hudson and Weaver escape Kowloon City, however, and use intel collected from Clarke to go to Mount Yamantau in the Ural Mountains.

DMZ
Mason's team and the Marines then head out to Vietnam's DMZ, where they were shot down. The team then has to clear a village and destroy enemy anti-aircraft guns to permit American helicopters to fly through. The Americans then clear out the north part of the village and go through rat tunnels, where Mason finds intel on Nova 6 and escapes the tunnel, which was rigged to blow up by Kravchenko.

Laos
The American forces begin an attack around the Laotian-Vietnamese border, and Mason's team uses a boat to attack the Vietnamese forces from the river. After the team destroys the enemy forces around the river, they move up and investigate a crashed plane that the CIA had discovered contained Nova 6. All of a sudden, Soviet Spetsnaz forces attack the crash site and the SOG team has to defend it. The team defends it until a Mi-24 Hind fires a rocket at the fuselage. This causes the plane to fall down a cliff and Kravchenko and Dragovich capture the team. After being captured by Dragovich and his men, Mason's team is sent to play Russian Roulette. Bowman is killed after refusing to play. Mason did not play, but he instead took the weapon and killed a Vietnamese soldier, then used the soldier's gun to kill the other soldiers in the tunnel. After Woods and Mason escape the tunnels, they take an enemy Hind, and they use the Hind to fly to a hidden Vietnamese base. Woods and Mason move through until they find Kavchenko, who hits Mason with a chair and beats him until he is stabbed by Woods. Kravchenko then pulls the pin on a grenade and jumps out a window with Woods, presumably killing them both.

Mount Yamantau
The CIA team at Mount Yamantau has orders to destroy a communication station. After the team destroys the station, they move out and discover a Nova 6 facility, where they receive a recorded message from Friedrich Steiner. While in the facility, it gets attacked by Spetsnaz forces and the team escapes while an avalanche buries the entire facility.

Rebirth Island
With Woods and Bowman dead, Mason heads out to Rebirth Island to kill Steiner. Mason creeps through shadows and kills anybody between him and Steiner. Meanwhile, a joint United States Marine Corps/CIA team, led by Hudson and Weaver, fights through the streets to Steiner's lab. The Spetsnaz spray Nova 6 on the streets and the American forces use their HazMat suits to survive. Once the team finally reaches Steiner's lab, they are shocked to see Mason about to kill Steiner. Weaver and Hudson attempt to stop Mason, but Mason shoots Weaver's arm and kills Steiner.

Revelations
After being brought to interrogation by the CIA, Hudson lets Mason free, but Mason punches Hudson and walks through the Pentagon until finally realizing what happened to him at Vorkuta. Hudson catches up with Mason and tells him what really happened—that Reznov was dead, he had been brainwashed, and was the only one who could translate the message encoded in the numbers—and so Mason agrees to try to translate the numbers one more time. He says that the numbers are being broad-casted from a Soviet ship in Cuba called the Rusalka.

Redemption
The team then assault the Rusalka via helicopters, and then lands. They move through the ship looking for where the broadcast station is, and they find out that the ship was converted to a submarine pen, with the broadcast station in the pen. Mason and Hudson, along with, Maestas, Aziz, and Drew, dive down to stop the broadcast and kill Dragovich. While down there, Mason finds the station and shuts down the broadcast, and kills Dragovich. After swimming to the surface as American jets bomb the Rusalka, Weaver says to Mason that they have won, but Mason replies that they have only won for now.