Charlie is a adult with a I.Q of a 68. He is mentally challenged and wants to be smart. He had a hard childhood, and people ignore him throughout his life. However Charlie doesn't know what is going on.
Professor Nemur did a operation on a mouse that made the mouse intelligent. So professor thought that Charlie should have the operation. Charlie agreed as well.
Charlie began to get smarter and started to notice things about life. He starts to become a different person and people started to leave him. Charlie realizes how people were being cruel to him. Also, Algernon the mouse for the experiment died.
Charlie's IQ starts coming back to normal because the operation only made Charlie temporarily smart. Charlie looses his memory, and starts to forget how to read and write too. Because of his memory lose and his decreasing IQ, he has to say goodbye to everyone and Miss. Kinnian.
Charlie writes letter to Miss. Kinnian and he finishes his progress report. Before he moves out of New York and goes to Warren Home his last wish is to put flowers on Algernon's grave.