Sometimes, the best movie can come from the simplest idea. Toys coming to life, a shark attacking a bay, or a day in the life of shop clerks aren't exactly mind-boggling or hugely original, but when executed well, they make for a films that are magical, thrilling, or just plain hilarious.
Then there are those films that have a ridiculous idea that really shouldn't work but which somehow works perfectly. Which is usually the case with pretty much everything Phil Lord and Chris Miller have done.
Inevitably, when a film has a high-concept or really interesting premise it can represent a massive risk, but promises a huge reward. Bold dice throws like Inception and Looper can result in some of the best movies of the decade so far.
However, not every movie can be an Inception and some incredibly intriguing concepts have been wasted in the execution.
Whether it's thanks to studio interference, poor acting and directing choices, or just a messy script, Hollywood has the potential to take what sounds like a fantastic idea and turn it into something completely different, and often something terrible.
10. Elysium And Chappie
The Premises: Elysium - set in the year 2154, the wealthiest members of society live in safety and comfort above Earth on a man-made space station, while the rest - i.e. those who can't afford it - are left to survive on the ruined remains of the planet. One man, though, will attempt to bring equality.
Chappie - In a future where the world is policed by robots, one is stolen and reprogrammed, becoming the first of its kind to learn and think for itself.
What Went Wrong: Neill Blomkamp, and to an extent, District 9. The director made a debut film that was both a superb sci-fi film and a nail-on-head social commentary. The expectation, then, was that he'd be able to repeat the trick, and was given a much bigger budget to do so with Elysium.
That didn't really work out. While it could have been another film dealing with sociopolitics, the widening gap between the haves and have-nots an extremely timely and important issue, it never made the most of it.
Instead, the idea was all too blatant and generic, and the movie devolved into more standard sci-fi fare - not bad, but not what it could have been.
The same can be said for Chappie. The idea of robots developing their own thoughts is nothing new, but putting that in the context of a police force, and then into the hands of gangsters, was fundamentally interesting, but ended up a bit of a confused mess.
In attempting to deal with various themes but didn't actually manage any of them, and had characters that were one-note, stereotypical, and annoying.