The Truman Show is about a man named "Truman Burbank" who is born into what he believes to be the real world but who is instead living in a simulation or deception that revolves around him personally. Truman is living in the only world he has ever known from birth and for the majority of his life he has no clue that he is actually living in a simulation. He is entirely brainwashed from birth to believe that he lives in the real world, or the only world that exists. He believes that everyone else living in his world is authentic and genuine when in reality they are part of the deception.
Although Truman is not supposed to know that he is living in a simulation, various people in the simulation try to give him hints about it but poor brainwashed Truman just doesn't get it. He is too brainwashed into believing in the reality of the illusion to understand the hints that are being given to him.
For most of Truman's life he has no clue that he is living in a deception but then he begins to notice things around him that are not right that reveal the deception to him. The more closely he looks, the more he realizes that he is indeed living in a simulation or illusion or deception and that everyone he thinks he knows is part of the deception, including his wife, his best friend, his work associates and his neighbors, even his own birth family.
At some point in his life he wants to escape the illusion and he tries to escape it. What he discovers when he does this is that all kinds of obstacles suddenly appear in his path to prevent him from escaping. Truman sees the obstacles as being part of the deception and he tries to go around them but soon the obstacles become too big and he is temporarily forced to go back into the illusion to attempt to plan an escape that cannot be blocked. He pretends to go along with the illusion but inside he is secretly planning his escape which he will tell nobody about around him because he knows nobody around him can be trusted.
Eventually Truman's persistence to escape allows him to escape the illusion/simulation/deception and to go into the real world, which he discovers is nothing like anything he could have imagined while living in the deception. The truth about the real world was kept entirely from him and he only discovered it after leaving the illusion. Everything he thought he knew inside the illusion had no reality outside the illusion and he had to learn a completely new reality after his escape.
Who is running the deception/illusion/simulation/dream and for what ultimate purpose does it exist?