There are actually several film versions of Sophocles' play Oedipus Rex, and they do contain some significant differences from the original play. We will focus on the 1957 and the 1968 versions of the movie for our discussion.

The 1957 film directed by Tyrone Guthrie uses a translation and adaptation by William Butler Yeats, which is already a variation on the original due to its deliberate modernization of the language. The film adds a narrative of explanation at the beginning that is not in the original play (which has the traditional prologue) and a conversation between a group of Thebans that is also not found in the play.

The 1957 film leaves out some important moments as well, including Oedipus' curse upon himself and Creon's speech about doing things against his will to become king. Oedipus does not ask for a description of Laius in the film either. Rather he wonders about Zeus' plans for him.

The film version of Teiresias lies on the ground for some of his lines. He would be standing in the original play. There is no boy to guide this blind prophet in the film either, which is rather strange because it de-emphasizes Teiresias' blindness. Finally, the chorus usually does not speak in unison in the film version as it does in the play. In the film, the chorus' lines are given to members of the crowd.

In the 1968 version, the film actually shows the murder of Laius and adds a scene of Oedipus and Jocasta in bed. The actors do not wear the traditional Greek drama masks in this version. This version is based on Paul Roche's translation of the original play. This translation uses a modern idiom to increase understanding of the themes.