In Command & Conquer: Red Alert 3 hopeless leaders of a doomed Soviet Union travels back in time so that they can change history. A new alternate timeline appears where the Soviets now find themselves as the leading superpower but also discover something else has gone terribly wrong. World War III is raging, the Japanese Empire of the Rising Sun has risen in the east challenging the Soviet bid for world domination. A three-way war now emerges between the Soviet Union, the Allies, and a new Empire of the Rising Sun faction.
The game follows the tradition of the Command & Conquer series where the player must build up bases and produce a massive attack force to destroy all enemies. The player may choose any one of the three factions, each with a different array of infantry, armored vehicles, aircraft, ships to fight with, as well as buildings with new technologies, upgrades, and the all-powerful superweapons. Players do all their building from a sidebar, this allows them to create production queues and deploy structures fast and easily.