Julius Caesar lands in Britain, where a small village still holds out bravely against the Roman legions. But the situation becomes critical and the villagers have not got long to live; that's when Jolitorax, one of the villagers seeks volunteers to go seek help from his second-cousin Asterix the Gaul and bring back a barrel of "magic potion" from the Breton village of the indomitable heroes.

Asterix and Obelix: God Save Britannia (French: Astérix et Obélix: Au service de sa Majesté, translated as Asterix & Obelix: On Her Majesty's Service) is the fourth film adaptation of the adventures of Astérix after Asterix & Obelix vs Caesar, Asterix & Obelix: Mission Cleopatra and Asterix at the Olympic Games, directed by Laurent Tirard. The film is adapted into 3D and had its World Premiere in September 2012. It is a live-action film from Fidélité Films. It is based on Asterix in Britain and Asterix and the Normans.