According to Plutarch, a seer had warned that harm would come to Caesar no later than the Ides of March. On his way to the Theatre of Pompey, where he would be assassinated, Caesar passed the seer and joked, "The Ides of March are come", implying that the prophecy had not been fulfilled, to which the seer replied "Aye, Caesar; but not gone."

Idus Martii is a hidden role game for 5 to 8 players. Players are members of the Senate who must plot in favour of or against the magnicide of Julius Caesar. But it is not that easy, as they need to identify who shares their convictions in order to partner against the other players...whilst keeping a look out for those only looking to fatten their purse.