Created by award-winning writer Jez Butterworth (`Spectre', `Jerusalem') `Britannia' is set in AD43 when the Romans invaded Britain led by General Aulus Plautius, who is determined to succeed where Julius Caesar failed and conquer this mythical land on the very end of the Roman Empire. Kerra, daughter of the King of the Cantii, is forced to put her differences with arch-rival Queen Antedia aside in order to unite the tribes and supposedly magical Druids and face their invaders. However, General Aulus carries a secret which threatens to undermine the entire mission.