The mood throughout Caesar and Cleopatra oscillates—often quite rapidly—between humorous, philosophical, and ominous. Over the course of Acts 1 through 3, Caesar's relationship with Cleopatra leads to many humorous and even heartwarming moments, contributing the general comedic air of the play. A large part of this joviality is due to Caesar's unwillingness to take himself and others seriously: he remains calm and collected when others lose their heads, almost to the point of hilarity.
As the central male protagonist, Caesar's joviality dictates the overall energy of the play in any given scene. Consequently, when his mood shifts—as it is wont to do, often quickly—the mood of the play will turn on a dime. Caesar will consistently take the opportunity to reprimand others for behavior he considers unacceptable; furthermore, he is prone to bouts of philosophizing, a tendency which establishes the play's more contemplative mood.
Finally, it is important to note that foreknowledge of Caesar's death and the events of Antony and Cleopatra infuse Shaw's play with an ominous mood throughout, though this occurs at a metatextual level. For the most part, audience members remain uninfluenced by this aspect of the mood, until future events are foreshadowed, bringing the metatext into the play.
