Based on a true story during the Civil War, The General starts with Buster Keaton playing Johnnie Gray, a talented train engineer from the South who has two loves of his life – his engine, and his girlfriend, Annabelle. As Johnnie is courting Annabelle, her brother and father get word the Civil War has started so they are going to volunteer for the Confederacy. Johnnie is guilted into enlisting also.
During the enlistment, Johnnie is determined by the powers that be he is more valuable as an engineer than as a soldier so he is told to go away with a swift kick to his caboose. But Johnnie doesn’t know why he was rejected. Annabelle’s family see him and believe he is a coward for not joining so Annabelle and her family tell him they don’t want anything to do with him anymore.
Fast forward one year…Johnnie is still engineer on The General. A plan is hatched by the North Army’s Captain Anderson to steal The General and as they make a run for the north, they will knock out telegraph lines and damage tracks so the Confederacy has no supplies. As they steal The General, they accidentally take Annabelle prisoner. Johnnie gives chase with several townspeople but they stop running as Johnnie runs into the distance, but doesn’t realize he is alone in his pursuit.
Johnnie, finally realizing he has no one but himself, ends up using a handcar, then a wooden boneshaker bicycle then finally reaches The Texas, another near identical engine to his beloved General. As he sets off in fast pursuit, the spies are dismantling the telegraph wires and sabotaging the tracks in numerous ways to stop Johnnie from catching them.
At one point, Johnnie picks up a large cannon that becomes more of a danger to Johnnie than to the spies ahead of him. Through many spectacular life-threatening stunts, Johnnie finally closes in on the spies, only to realize too late he has driven right into deep enemy territory and he has to abandon The Texas to escape for his own survival.
In the middle of the night, Johnnie sneaks into the North’s headquarters and overhears a surprise attack is planned on the Confederates and realizes Annabelle is a prisoner in the house. Johnnie uses quick wits and costume changes to rescue Annabelle and steal The General and race back to tell the South before they are killed.
As our heroes head back the same way they just came, they are pursued by not only the spies in The Texas, but also the entire North army! Johnnie and Annabelle set all kinds of crazy traps and stunts to slow down the bad guys, including at one point ending up switching rails and ending up behind them! But they race off and finally set fire to the train tracks over the river as they arrive at the town to tell the Confederates about the attack.
As they North finally attacks, the Confederates are ready. In a large battle sequence across the river, the North decides to drive The Texas over the bridge. As the huge engine chugs forward, to everyone’s surprise, the bridge disintegrates and the entire twenty-ton engine falls into the raging river below. The disaster turns the tables of the battle. Johnnie joins in the battle and nearly single-handedly defeats the North.
After the North retreats, Johnnie comes back to a hero’s welcome, but it’s for the soldiers and not him. As he disappears into the crowd, he realizes he has accidentally captured a 4-star North general on his engine. As he marches the prisoner away, he is taken aside by the South general and commissioned as a Lieutenant in the army for his bravery in front of Annabelle and her family. He finally gets the girl and the engine.