Caesar and Brutus were walking in the streets. Caesar hears someone calling his. He tells them to speak up, and a soothsayer tells him, "Beware of the Ides of March."
Caesar was worried about the Ides after his wife had a dream. He had servants read an omen. Later Caesar asked what the omens read, and the servant said that the chicken had no heart. This was a bad sign.
Caesar went to the Senate House on the Ides. He. starts getting stabbed by Cassius and the men he recruited to help. Caesar feels betrayed because even Brutus, someone he saw as a brother, was helping with his murder.