What are the main ideas in act 1?
In Act I scene 1, Caesar returns to Rome after the death of Pompey. The Tribunes are nervous about his return as Caesar returns as the most powerful man in Rome. They try to end the celebration for his return by reminding the city that Pompey died a loyal Roman during the civil war.
In scene 2 Caesar is heading towards to the coliseum for the annual footrace. He is stopped by a soothsayer, fortune teller, who warns him to beware of the Ides of March. Caesar brushes him off and continues to the race. Cassisus and Brutus stay behind to talk. Brutus is worried that the people have chosen Caesar to be the king, so Cassius warns him that he must do something to stop him. Antony offers Caesar the crown three times, but each time Caesar turns it down.
In scene 3 Casica, a conspirator against Caesar, speaks with Casaca about the dark signs he has seen (a hooting owl, a lion in the capitol). Cassius tell Casaca that he would rather die than see Caesar be king and tells him about the plot to kill Caesar. He says that Brutus is almost on board, but needs a little more convincing.