The fantasy genre is home to all of the most colourful and imaginative ideas filmmakers have to offer, and the worlds that reside within are often so far removed from our own that the rules that we know seem to have little standing.
That said, all stories at their core are about the characters that reside within them, and the decisions they make.
Moments of tension usually spring from someone onscreen making a truly awful decision, like stepping outside into the dark of night immediately after receiving a threatening message, or walking blindly into danger despite countless warnings.
Equally, though, there are times when these movies make some truly brilliant decisions, and sometimes in ways that we as an audience hadn't even thought of. There's no better feeling when watching a movie than having one of the characters come up with a solution that not only makes sense, but was also completely unexpected.
There's also plenty of examples of wise decisions made on the other side of the camera, though, and the filmmakers often deserve some credit for their part in choosing to do something that paid off well for everyone involved.
10. Recasting Tony - The Imaginarium Of Doctor Parnassus
The Imaginarium of Doctor Parnassus almost never reached our screens.
Due to the tragic and untimely death of Heath Ledger halfway through filming, writer and director Terry Gilliam didn't think there was any way of finishing the movie. Added to the fact that Ledger's presence was vital in securing the movie's financial backing, it really seemed to be the end for The Imaginarium of Doctor Parnassus.
When Johnny Depp, Jude Law and Colin Farrell - all friends of the late Ledger - agreed to step into the role, a simple rewrite had each of them playing different versions of Ledger's character while in the movie's "magical realms".
It may seem like a convenient write-out, but it actually worked remarkably well in relation to the rest of the movie.
Maybe it's due to The Imaginarium's dark magical tone, or maybe due to the pedigree of the stand-ins, but it felt like a natural way to proceed with the movie while honoring Ledger's memory.