On the manor farm, Old Major, gathers the animals for a meeting and inspires them to revolt. Although he dies, two pigs, Napoleon and Snowball, vow to continue his work, and lead the others in driving off the unfit, drunken farmer. THe pigs of the farm begin to establish a new government where pigs have rights.
The animals begin to read and write and have beliefs. They use the commandments to educate all the young. Food is plentiful, and the farm runs smoothly. However, when the pigs elevate themselves to positions of leadership, a struggle for power begins. Napoleon wins by having his dogs chase Snowball off the farm.
As supreme leader, Napoleon enacts changes to the governance of the farm, replacing meetings of all animals with a committee of pigs who will run the farm. Eventually, Napoleon's supremacy has him paranoid that someone will try to overthrow him.
Napoleon begins to blame Snowball, the pig he chased away, for incidents happening on the farm. Using a Snowball as a scapegoat, Napoleon begins to purge the farm, accusing other animals of conspiring with his old rival, and attacking them with the dogs.
The animals become convinced that they were better off with the farmer, Mr. Jones, than the tyranny that has come to be. Things get progressively worse on the farm. Animals are worked to the point of collapsing, and it is clear that the commandments have been rewritten.
Animals are no longer equal. The pigs are beginning to take on human qualities- like walking upright. As animals gaze at pigs and humans, they realize they can no longer tell the two apart.