Brutus, Cassius, and the rest of the conspirators meet up. Cassius suggests that they kill Antony as well, but Brutus disagrees.
Oh no Caesar! Why would you do this to him?
We did it for Rome!
Caesar had planned on going to the Senate, but Calpurnia tells him about her dreams and insists that he doesn't go. He planned on staying home until Decius, a conspirator, convinced him to attend the Senate that day.
It's not that I loved Caesar less, but that I loved Rome more.
Caesar enter the Senate and is surrounded by the conspirators. They proceed to stab him, with Brutus delivering the final stab.
Brutus and Cassius are traitors!
When that the poor have cried, Caesar hath wept!
Antony hears about the death of Caesar and enters. He asks the conspirators to kill him as well. They do not, and Antony asks if he can speak at the funeral. They let him, but only if Brutus speaks first.
Brutus tells them that he killed Caesar out of his love for Rome, and that Caesar was too ambitious. The people side with him and believe that Caesar was bad.
When Antony talks to the people, he tells them about all the good Caesar brought to Rome, and he convinces him that Caesar was good. The people turn against the conspirator.