In Act one, Scene 2 Caesar was offered a crown three times after the race of the Feast of Lupercal. Caesar refused, but according to Casca "he was very loath to lay his fingers off it" (I:ii:ln 240-241). This is the most important scene because it basically fuels the conspirators ambitions towards Caesar. The people didn't support him being king either, but they are easily swayed.
Act IV: Sc 3
Thou shalt see me at philippi!
In Act 2, Scene 1 the conspirators go to Brutus' house and ask for his help in killing Caesar. Brutus agrees, reluctantly, by saying "No, not an oath. If not the face of men, the sufferance of our souls... ...that this shall be, or we will fall for it?" (II:i: ln 114-128) This is important because when Brutus joined the conspirators, it really put their plan into motion. With his guidance, they were sure to succeed.
Act V: Sc 5
This was the noblest Roman of them all
In Act 3, Scene 1 Brutus literally backstabs Caesar. Brutus is a likable person to everyone, even to Caesar. So, when Caesar finally realized that Brutus was a part of the group, he knew he had to die. "Et tu, Brute? Then fall Caesar!" (III:i: ln 79). This is the turning point of the whole play and sets the rest of the story in action.
Theme Act III : Sc 2
I would easily kill myself as I did to Caesar, if it were to be for the better of Rome.
In Act 4, Scene 3 inside Brutus' tent the ghost of Caesar visits him with a grave warning. Caesar tells him "thou shalt see me at Philippi" (IV:iii: ln 283). This is the most important line in scene 4. It gives a blatant foreshadowing of what is to come at their battle in Philippi the next day.
In Act 5, Scene 5 Brutus and Cassius have lost their battle, their only option is suicide. Brutus then jumps into the same blade used to kill Caesar. When Antony finds his dead body he goes on to say "This was the noblest Roman of them all" (V:v: ln 68). This line ends the play with Antony showing his respect to his former enemy, Brutus, thus making him a true Shakespeare tragic hero.
The theme of the story is that all great actions have great consequences. This is true because the conspirators killed Caesar and they all ended up dying. Even Brutus said during his speech "I have my same dagger for myself, when it shall please my country to need my death" (III:ii: ln 47-48). So even Brutus knew if what he did was wrong, he would easily take his own life for the same reason he took Caesar's. for the greater good of Rome.