‘What did the Romans ever do for us?’ A question immortalised by Monty Python and coyly repeated by a disgruntled Celt in Horrible Histories: The Movie. Played with a nod and a wink, this comedic open goal says all you need to know about the arch, playful and endearingly silly streak which has made Horrible Histories such a phenomenal success.

Whether it was the magazines, well-thumbed books or TV series, the franchise has bounded across time engaging kids and parents alike. Just as the same crew saw great success with the endearing Bill, the main show’s transition to the big screen is a vibrant romp.

Rotten Romans begins in resplendent Rome but then spends the majority of its time in the much more prosaic – and hey, much cheaper – Britain. In switching locations, we follow Atti (Sebastian Croft), the quick-witted teen forced into service as a Roman soldier. Unwilling to fight, he crosses paths with Orla (Emilia Jones), a feisty Celt who wants to be a warrior. While the teens’ two worlds collide, there’s an uprising afoot, with Boudica (Kate Nash) intent on toppling the petulant Nero (Craig Roberts).

To all intents and purposes, the film is a pantomime, bulging with caricatures, comedic motifs and sing-and-stamp-along songs. The latter component, in particular, is when the film shines most vividly. There’s a Spice Girls-esque power anthem belted out by Kate Nash, an Elton John-inflected romp for the Emperor and a perfectly soppy teen ballad for the SPQR-crossed lovers. Even in the moments when the film’s momentum slows, the music injects life into the narrative.

While the music is an intermittent treat, the ensemble cast are a constant source of comedy. Nick Frost and Kim Catrall are excellent as a celtic leader and Agrippina, while Lee Mack’s general is gifted a comedic beat which keeps on giving. There’s even space for a scenery-chewing Rupert Graves as the Governor Paulinius, who pines for glory while always referring to himself in the third person.

Though the film is less intently pedagogical than the TV show, there’s enough here to suggest it could spawn an equally successful series of films. All the component parts are there for a Carry On-esque series, albeit with less sexism and more musical numbers. Though Rotten Romans is perhaps a shade too long – with the middle section in particular feeling bloated for younger audiences – it’s got enough in there to keep kids entranced and parents amused.