Horrible Histories: The Movie - Rotten Romans (PG, 92 mins)

Director: Dominic Brigstocke

Stars: Emilia Jones, Sebastian Croft, Craig Roberts

3 stars

With scenes that alternate between the factual and the flatulent (and frequently both at once), it’s probably best left up to the individual viewer to decide whether Horrible Histories is first and foremost a history lesson or simply an excuse for all manner of silliness.

Based on the multi-million selling series of Terry Deary books and spinning off from the popular CBBC show, this clever and daft hodgepodge has rather abandoned the TV cast - who were perhaps all too busy making sitcom Ghosts - in favour of lesser known young leads and starry cameos.

But that does allow for the likes of Derek Jacobi to pop up and spoof his own star-making role in I, Claudius as the dying Emperor. Craig Roberts and Kim Cattrall have a whale of a time as the petulant Nero and his scheming mother Agrippina, and much of the funniest stuff takes place in the Emperor’s throne room.

It’s Nero who sets the plot in motion by forcing young Roman lad Atti (Croft) into the army and banishing him to the Empire’s furthest and least illustrious outpost, Britain, where he’s taken prisoner by ambitious teen Orla (Jones). This all coincides with the rise of Boudicca, who is running riot with her rebellion and trying to unite the Celtic tribes against the Roman invasion, as detailed in a couple of fun song and dance numbers.

Elsewhere, Roman numeral gags abound, there’s tons of clever background detail that would be very easy to miss and, given the pace at which the jokes are fired off, it’s fairly impressive that only a limited number of them turn out to be Life of Brian knockoffs.

Though Jones and Croft are the nominal stars - and they make for a likeable duo - they’re not really called upon to do the heavy comedy lifting. That’s left mostly to the terrific Roberts, while Lee Mack gets decent mileage as a wistful centurion forever dreaming of the far off hills of Rome. And being Horrible Histories, there’s absolutely no shying away from the lavatorial side of things, with poo and pee plentiful and, of course, entirely historically accurate.