Arthur Curtis is a businessman planning a vacation to San Francisco with his wife. After arriving at his office and talking with his secretary Sally, he discovers his office to be a set on a sound stage after finding that his telephone is not functional, and hearing someone yell "cut". He is told that Arthur Curtis is merely a role he is playing, and that his real identity is Gerald Raigan, a movie star who is caught in the middle of a brutal divorce from a hostile wife, his own alcoholism, and a declining career. He leaves the studio with his wife as she wants money.

He tries in vain to locate Arthur Curtis's house, and mistakes a little girl for his daughter, scaring her. His wife drives him to their actual home. Inside, he meets his (Raigan's) agent, who tells him that if he doesn't continue work that day, he will drop him as a client. Curtis still protests that he is not Raigan, and tries to call his workplace, but the operator can't find any listing of it. His agent believes that he is having a nervous breakdown, and shows him the shooting script of a movie called The Private World of Arthur Curtis. He then tells him that the movie is being cancelled due to his outburst in the studio.

Raigan/Curtis rushes back to the set, which is being dismantled, and pleads not to be left in the uncaring world of Gerald Raigan. Curtis reappears in his office as it was before, just as his wife arrives. Sally gives Arthur his plane tickets. As Arthur hears echoes of the studio sounds, he tells Marian that he doesn't want to lose her and that they should leave for their vacation immediately. Meanwhile, in the "real" world, Raigan's agent shows up on the set to find that Raigan has vanished. As the set is being dismantled, a teaser shows the "Arthur Curtis" script left on a table, waiting to be thrown in the rubbish bin. In the last scene, Curtis and his wife board a plane, which takes flight and fades away into the sky.

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