Brutus comes up with the plan that Caesar must die whilst he is in his garden.
Brutus sends his servant Lucius to light a candle in his room. Lucius returns with a letter he's found. The letter says Brutus should recognize his own noble nature and do something before Rome falls to the tyranny of a monarch.
A group of conspirators show up at Brutus' door and try to win Brutus to their cause, Cassius introduces all of the conspirators and Brutus welcomes them into his home.
Cassius then suggests they also kill Antony (Caesar's young friend) while they're at it.Brutus disagrees, thinking that would be overkill. He talks about how they should murder Caesar nobly, carving him up like a dish for the gods, not like a "carcass fit for hounds."
Cassius points out that Caesar has been cautious lately because of all the bad omens floating about. Cassius further worries that Caesar's prophets might convince him to take a sick day from the Capitol.
At first, Decius tells everyone not to worry; he'll show up at Caesar's place in the morning to make sure Caesar goes the Capitol. Then Brutus decided that everyone will meet at Caesar's to make sure he shows up at the Capitol for the murder.