Your Highness sounds like something a bunch of drunk or otherwise incapacitated film students might come up with (and in fact was actually conceived by Danny McBride and David Gordon Green in their undergraduate days). If you take a generic sword and sorcery adventure, populate it with fratboys and their penchant for silly antics, F-bombs and cusswords, and shoot it as a slacker comedy, you might end up with something the Wayans brothers might have thought up if they were more competent writers and comedians. Or something the king of crass comedies, Wong Jing, would have done if he went from Hong Kong to Hollywood instead of China.

So while an evil sorcerer kidnaps a beautiful maiden in order to complete a once-in-a-century arcane ritual and gain enough power to destroy the realm, our heroes must undergo several trials to seek a sword that will pierce the sorcerer’s magical armour and slay him. From such a generic beginning, we throw in a brawny but slightly stupid prince (Franco) and his lazy, obese but smart brother (McBride), and allow both actors and their supporting cast (notably Natalie Portman and an animatronic puppet) to ad lib their way through a collection of hilariously mismatched studio fantasy sets.

With enough crass jokes, F-bombs, sight gags involving giant phalluses and even a Michael Jackson paedophilia reference, Your Highness achieves the status of an entertaining and memorable comedy. Your mileage will vary depending on how easily amused you are by cusswords and F-bombs and your disposition towards slacker comedies.

Your Highness is one of those concept comedies that should delivered far more laughs, given the involvement of McBride and Green. While genuinely funny in itself, it doesn’t deliver its promise of deconstructing the sword and sorcery genre. It’s also arguably the least self-conscious performance we’ve seen from Natalie Portman so far in her manic “five films in two years” phase. I’d argue that she has far more comic talent than dramatic talent, and that Franco doesn’t do badly either.