7. The Dark Knight Returns (1999)

While scrambling to work out what the Hell to do with Batman, Warner Bros. did flirt with the idea of adapting Frank Miller’s much-loved, super-dark graphic novel, in which a 55-year-old Bruce Wayne comes out of retirement to fight crime once again.

It’s an extremely bold move – one unexpected for Warner, no less – as it would have dispensed entirely with what we expected from a Batman film, and of all people, Joel Schumacher was extremely keen to adapt it, especially in the wake of Batman and Robin flopping.

Clint Eastwood and Michael Keaton were apparently both considered for the role – the former sounds amazing, the latter would simply have been a case of “too soon” – while David Bowie’s name was again thrown around for The Joker.

So, what happened? Regrettably, despite so many great names being thought about, it never came of anything, as Warner Bros., in their infinite wisdom, seemingly weren’t too keen to listen to Schumacher after Batman and Robin’s failure.