A tale of moral choice based on Racine's play of 1669. Britannicus, son of the Roman emperor Claudius, is heir to the imperial throne. His succession is however brutally usurped by his half brother Nero, son of Claudius' wife Agrippina. Agrippina is portrayed as a possessive mother who will not accept the loss of control over both her son and the Empire. Nero's true nature is revealed by his sudden desire for Britannicus's fiancee Junia. His desire for Junia manifests itself in sadism towards the young woman and all that she loves.