Brutus tells Cassius that he hears shouting and he fears that the people have choose Ceasar as their king. "What means this shouting?"(I:ii:ln79).
Act IV: Scene:i
They are planning to kill Caesar and Trebonius will be by Caesar's side. "Caesar, I will [aside] you and so near will I be, that your best friend shall wish that I had been further"(II:ii:ln124).
In this Act They all go and meet Caesar and they kill him, and Brutus and Antony go and tell the towns people about the death.Brutus asked the people if he offended anyone and they said no. "Then none have I offended. I have done no more to Caesar than you shall do to Brutus...Where in he was worthy, nor his offenses, for which he suffered death. " (III:ii:ln 36-40).
Brutus thought he was doing good for Rome
Antony and Octavius say that Brutus and his men must die for killing Caesar. "These many then shall die; their names are pricked"( IV:i:ln1).
Brutus gives the call to war, Cassius gets killed Brutus dies after asking 3 different people to kill him, they say Brutus truly was an honorable man. " This was the noblest Roman of them all...This was a man"( V:v:ln68-75).
Brutus killed Caesar because they though he was gonna turn evil but it just back fired on him."Farewell good Strato - Caesar, now be still; I killed not thee with half so good a will"(Theme :ln50-51).