Modern Warfare 4 takes place one year after Modern Warfare 3 takes place. Salmon is shipped to the S.A.S., where they support Task Force 141, lead by Major MacTavish.
- Russian Armed Forces
- Terrorst Forces
- Chinese Armed Force
- Russian Terrorists
- Task Force 141
- Australian Armed Forces
- American Armed Forces (Act II onward)
- Makorav's Forces
- Brazilan Militia
- Al-Asads Avengers from the East
Act I: With the war going hard into Russia, Colonel Candler nominates the Hawaii Reserves to join the fight against the Communists. A Russian spy catches word of this, and to stop them blows up C4, killing Candler and stopping the Americans.
However, Captain Price of the SAS has been captured by the Chinese, so Soap and Salmon go in to rescue him and as they do they find a crazy SAS troop, dressed in all black. After interragation, they find that this troop, lose nearly eight years ago is Gaz, who went crazy to do a brain problem.
Escaping from China, they find Shadow Company has gone big in the American Armed Forces. Raiding in, they find that Gold Eagle is near the base and is wanted by the SAS. Price is again captured, this time by Shadow Company. The Task Force gives chase, and evantully crash, while killing Gold Eagle, and finding out what happened to troops named Seargeant Roach Sanderson and Ghost, who Gold Eagle personally executed.
Finding bomb plans in Washington D.C. and while Gaz and Price torture and kill Shadow Company's new leader, and strongly torture the President of the United States, they know it's a hundred miles from Rio de Janerio, as the find the bombs complete plans and send it to the U.S. Army Rangers, for proof and to fight against Shadow Company meanwhile Price and Gaz are captured by Brazilian militia. At the end of Act I, they find out that Shadow Company has invaded the United States and has claimed Maine as their own country.
Act II starts off with Lieutenant Foley's squad as they invade Shadow Company's America, with support from Sergent Dunn and Corporal James Ramirez,as they battle, they push back Shadow Company's forces deeper into Maine.
They continue to fight, as Ramirez shows Mactavish around a Shadow Company base killing officers, as they fight through the streets. There they meet some Marines, who are also paid to fight for Shadow Company, as they knock down Mactavish and Ramirez, as they whip them both with their rifle butts. Before Soap is executed after the beating Foley saves them, but the group is surrounded and Jake Dunn is almost killed, but barely survives.
The real Marines come in, and burn through Shadow Company, where two of the eight Marines, the rest of the thirty killed, are called as traitors, and can kill your Captain and wound a sergeant. They escape to a convey, where a Colonel almost kills Locke, the playable Marines, but Locke shoots the Colonel into his head, but dies of his gunshot wounds.
The SAS try to rescue both Price and Gaz, but they get to Price, they find out Gaz is going to be hung in two hours. Sneaking into the execution, as the trapdoor opens, they shoot the rope, but are to late as his neck is broken. Price executes everyone in the room, besides his SAS squad, and orders them to go.
Later on in Act II, it focous on taking out Shadow Company from Maine and ridding the world from Shadow Company's disgrace to America. Several Marines and Rangers turn to Shadow Company making the fight even harder, but they push Shadow Company into Canada, and evantual into Northern Canada, as the SAS leave the fight to rough up Russia for the long war in Russia, the third Civil War in nearly a decade.
Act III starts with the SAS attempting to get Moscow ready and weakned for the war, as they nearly bomb all of the cities buildings, and kill Russia's president, but not before Soap is lost in a mess up, and Kamarov is killed. However luckily for the Americans, they are great at pushing back the weak Shadow Company.
But, Shadow Company bombs the entire battlefield, as everyone but three Americans are burned. However Soap in Russia dreams of zombies, yet is woken up somewhere in the Middle East by Jamie Salmon and Price. There they meet Al-Asads Avengers from the East, a group of Chinese and Arabic terrorists, who capture everyone except Soap and execute Carmen, but fail to kill Salmon and Price, nor Soap as they are able to escape by raiding a vehicle storage building and escape on a Pave Low.