The central joke of Jonah Hill and Channing Tatum's follow-up 22 Jump Street is that sequels are by definition bigger and more complicated, but never quite as good as the original. Indeed, at every point the filmmakers one-up 2012's 21 Jump Street, from the fact that every crashed car explodes into a ball of flame to the new glass-and-steel headquarters for the undercover squad, just across the street from the old one.

22 Jump StreetJonah Hill [L] and Channing Tatum [R] in '22 Jump Street'

Clearly this is a theory that's been adopted by Marvel for their Avengers family of movies, as the stakes keep getting higher and higher. But once you've saved Los Angeles, New York, London and the entire planet, where do you go? So now we have Thor's inter-realm shenanigans. And they're pushing it into a new level with this summer's Guardians of the Galaxy.

Other franchises that are growing this summer include The Transformers (Dinobots!), How to Train Your Dragon (swarms of them!), Planet of the Apes (apes with guns on horseback!) and The Expendables (even more ageing action stars!).

More: read our full review of '22 Jump Street'

Perhaps the way forward is to echo the longest running franchise in film history. Sure, James Bond producers escalated the villainous threat until they ludicrously ended up on the moon in 1979's Moonraker, but it was when they returned to earth that the series became unstoppable. In 007's latest outing Skyfall, the baddie was just a guy with a personal grudge. And it became the biggest hit in the entire 50-year series. Marvel take note.

More: Jonah Hill defended by colleagues at '22 Jump Street' premiere