The action of the movie starts during the First World War when soldiers from Tomainia try to bomb the Notre Dame cathedral but unsuccessfully. The attempts are stopped when an air raid takes place over them. The soldiers are called to the trenches, being told that the opposing forces had broken through. The main character, a soldier still unnamed to this point fails to fight against the enemies and at one time even starts marching with them.
Then, he hears a man calling for him and the soldier discovers a pilot from his own country. The soldier gets into the same plane with the pilot and helps him fly it since the pilot was wounded. The two fly away just as the enemy closes on them and start firing at the plane. The pilot has important information which can change the course of war and he tells the soldier this in case something will happen to him. During the flight, it becomes clear that the pilot is in no shape to fly, passing out a couple of times. The plane crashes when it runs out of gas and they are told that the war was lost and Tomania defeated.
The first ten minutes of the movie presents war from a comic point of view which had the purpose of criticizing the army and the way they operated. The people in charge are portrayed as incompetent, the soldiers as not properly trained and the confusion on the battlefield as ever-present and the cause of unfortunate events.
After the war ends, a succession of newspaper clippings show the state of the country, ending with the mentioning of the economic depression and the rise to power of the Hynkel party, or rather the Nazi regime.
During this scene, it is also revealed that the soldier who saved the pilot was still a hospital, having no memory of what happened before the war. He was a Jewish barber whose name will never be revealed in the film and is only knows as ‘’Private’’. This general name used for the Jewish barber is used to transmit the idea that instead of being seen as individuals, the Jews were perceived as a group and as such, every Jewish person was in danger of being persecuted by the regime.
The first speech gave by Hynkel in the film summarizes the major ideas and beliefs of his party, namely the superiority of the Aryans and what qualities made a person an Aryan, the depravity of the Jewish people and the need to conquer the surrounding territories. The tone of the speech is violent but still the people who listen to it are trapped in a frenzy every time Hynkel stops talking, hailing their leader almost as a God. This image shows just how much the people believed in the ideas promoted by Hynkel and how they were willing to do everything their leader asked.
The next scene presents a group of soldiers going through the Jewish neighborhood. A young woman who can’t find work witnesses a group of soldiers robbing a Jewish merchant being robbed of his produce. The woman tries to stand up but the soldiers, who were now perched up in a truck, start throwing tomatoes at her.
While these events are taking place, the Private returns to his former neighborhood and to his barber shop which he is under the impression he left only a few weeks ago. The Private is surprised to see the state of his barber shop and then enters into an argument with a few soldiers who then try to beat him. The Private is saved by the young woman who stood up against the soldiers and she introduces herself as being Hannah.
These two scenes are used to show the brutality of the soldiers and the fear of the common people who decided to stand by and listen to the orders they were given. Hannah does not understand why the common people would not want to fight back against the soldiers but at the same time she is extremely cautious and tries to hide the Private when two other soldiers come looking for him. The two soldiers find the Private and he fight against them once more, throwing paint at them. A mob of soldiers find the Private and they try to hang the Private to a lamp post.
The commander, Schultz, comes along and surprisingly, is the same pilot the Private saved during the war. The commander takes the Private’s side and even makes sure he will not be harassed again, nor he nor any of his friends. This comes a surprise for the soldiers who never thought any of the Jews could be worth anything and capable of any type of bravery.
Then, the scene moves to Herr Hynkel, presented as always busy and always interested in new inventions which could help the war. However, none of the inventions are presented as having any type of value at all. In this scene it is also reveals that the people are becoming increase unhappy, the long hours and the bad pay making everyone tense. Hynkel also expresses his desire to invade foreign countries but a lack of many makes him rethink his attitude towards the Jews since he realizes he needs loans from them.
The situation in the ghetto changes for the better and the Private puts his business back on its feet once more. Business is slow because most of the Jewish men were sent to the working camps so the Private has to extend his business to women as well. Those who remained, thought about leaving the country, hoping to find a better life, a life where no one is looking down on them because of their race.
When Hynkel comes again on scene, he is told he must eliminate all Jews and then create the perfect Aryan race. Hynkel appears to be scared of the idea of becoming a dictator put the possible power he could have as a result corrupts him and he wants to rule the world, no matter the cost.
The Private continues to work, getting closer and closer to Hannah who is also attracted to him. The Jews in the ghetto keep their hopes up, thinking that things will become better in time and they even think they will be offered their rights once more. There are still many who refuse to believe good times will come and keep their pessimism.
Hynkel becomes more determined to get rid of the Jew but Schultz refuses to carry out his plan. Because of this, Hynkel becomes determined to punish Schultz and decides to send him to a working camp. Hynkel decides to address the Jews, presenting his hateful views towards the Jews. The people in the ghetto do everything they can to protect themselves and hide themselves from the soldiers they knew will eventually appear in their homes. The previous sense of peace disappeared in a minute and the soldiers began to vandalize the Jewish homes and business once more. The Private and his and his neighbors and friends are still protected but when the soldiers find that Schultz was arrested, the return for the Private, wanting to kill him.
Hannah and the Private find refuge on a roof and watch as the buildings around them are burning. Commander Schultz escaped from arrest and was hiding in the cellar of the building where the Private was living. He called a meeting, proposing a plan to get rid of Hynkel, be it at the cost of a human life.
However, they both refuse to accept the responsibility of blowing up the Castle where Hynkel lived. The next day, the soldiers came to the ghetto, looking for the Private and for Commander Schultz. The people who were hiding the commander asked themselves how much was he going to be there and just how much their lives were in danger. Despite all these worries, they still tried to hide the two when the soldiers came to their doors.
Eventually, the two men were captured by soldiers and were sent to prison camps. Hannah and her family escaped to another country where they both started working and living a relatively happy life in comparison with the one they had in their former country. Hannah kept in contact with the Private through letters, hoping to see one another again.
Hynkel prepares to invade Osterlich but is told that Napolini, the leader of the country Bacteria prepares to invade Osterlich as well. Hynkel is called by Napolini and the two meet and decide that Hynkel will be the one to invade Osterlich.
While these events are taking place, the Private and Schultz escape prom the prison camp and plan to escape to Osterlich while dressed in uniforms. At the border, the soldiers confuse the Private with Herr Hynkel and they salute him as their leader. The Private is put into a car and then he goes into Osterlich as Hynkel, invading the country. At home, the Jews are treated even more badly, some of them being killed in broad daylight. Hannah and her family are caught in the crossfire. The private is taken to the Osterlich capital where he gives a speech for the first time in his life in front of a whole country.
The speech gave by the Private gives the people hope. He talks about the former regime and militates for freedom. He urges everyone to fight for freedom not for oppression and to free everyone and make life beautiful for everyone. He urges everyone to fight against dictators and to fight against intolerance. The message is completely different from the ones given by Hynkel and this message reaches Hannah as well, who rises from the ground and looks towards the sky. The last scene is important, used as a message of hope for everyone and transmitting the idea that even though the present is harsh and violent, the future will always hold the promise of a better day.