Act I is centered around introducing the play and some of its characters. The play opens around a crowd of people waiting for Caesar's return after his victory over Pompey's sons. As the parade marches by, a soothsayer bids Caesar to "beware the ides of March." Later in Act I, Cassius persuades the frightened Casca to join the conspiracy during a violent storm. They both plan to visit Brutus later with fake petitions to help persuade Brutus to join the conspiracy.
Act II opens with Brutus contemplating whether to join the conspiracy or not when Lucius brings Brutus one of Cassius's petitions. Cassius and five other conspirators enter. Brutus agrees to become a conspirator, but refuses to take and oath, including Cicero in the conspiracy, and killing Mark Antony. Brutus then leaves with Caius Ligarius for the Capitol. Later in the morning, Caesar's wife, Calpurnia, begs Caesar not to go to the Capitol. He is finally persuaded to go by Decius. Mark Antony and the conspirators enter, and they all leave for the Capitol together. On the way, Artemidorus tries to warn Caesar of his impending death with a letter, which never makes it to Caesar. Portia sends her servant, Lucius, to the Capitol for news while she speaks with a soothsayer who will try to warn Caesar a second time.
In Act III, Caesar, along with the conspirators, makes his way to the Capitol. The soothsayer and Artimedorus both try to warn Caesar to no avail. He is killed at the Capitol,