Flavius and Marullus go to the towns people and yell, "Hence! Home, you idle creatures, get home! Is this a holiday? What, know you not, being mechanical..." (Act I/Scene i/Line 5/Pg.822), They think that they should be a work and not wasting the day celebrating Caesar's defeat of Pompeii.
Act Iv: Sc iii
Brutus is worried about what will happen to Rome whenever Caesar becomes the ruler. He plots with Cassius a plan to take over Rome and defeat Caesar. Portia Brutus's wife is concerned about Brutus, and wants to know what's going on. "Brutus is wise and, were he not in health, He would embrace the means to come by it." (Act II/Scene i/Line 255-260/Pg.849
Act v: Sc v
The noblest Roman of them all.
All the conspirators go to Caesar's house and convince him to go to work and they all walk him to work, Casca shouts, "Speak hands for me!" (Act III/Scene i/lines 75/Pg 863) and they begin to stab Caesar one by one, Caesar walks up to Brutus and see's that Brutus is apart of it, and then Caesar is heartbroken and then falls to his death.
Cassius and Brutus flee the town after Antony talks at Caesar's funeral. Cassius blames Brutus for everything that happened. They are yelling at each other, "You have done that you should be sorry for. There is no terror, Cassius, in your threats..." (Act IV/Scene iii/Lines 65-75/Pg 889)
Antony wins the war, Brutus took his own life, and threw himself into a sword for the people of Rome, because he made a promise to Rome that he would do his best for Rome. "This was the noblest Roman of them all. All the conspirators save only he did that, they did envy of great Caesar.." (Act V/Scene V/Lines 70-75/Pg 912
I think the theme would be not to judge people, and kill them.. Caesar could've been a good king, but we will never know because he got judged. Plus all of this started because Caesar got killed. Maybe everything could've been peaceful and maybe everyone didn't have to die."Caesar, now be still; I killed thee with half so good a will"(Act V, Scene v/ Lines 50/ Pg, 911)