The amount of work that goes into shooting a single scene in a movie - let alone the entire finished product - is incredible. There are all sorts of considerations to be made, including keeping framing consistent and correct, making sure timing is absolutely perfect, and enabling actors to do the very best job they can do.
The longer a scene goes on, the more likely it is that something will go wrong. The smallest of mistakes can render a whole scene unusable, and this is one of the reasons why scenes tend to last about ten seconds between cuts (even less during action sequences).
Which makes attempting to shoot a scene in one take an incredibly arduous and ambitious task. The ability to co-ordinate such a complex feat is what separates a good, competent director from a great one. It also singles out certain actors as being extremely capable, too.
Here's 8 of the very best...
8. Children Of Men - The Car Ambush
Though both of Alfonso Cuaron's more recent movies (and Gravity and Roma) could feasibly have made this list, Children Of Men is arguably a vastly more astonishing piece of work, detailing a future in which two decades of human infertility have left society on the absolute brink of collapse.
The film is known for its raw, visceral portrayal of society in its death throes, and contains a bunch of long, unedited scenes. But undoubtedly the most memorable and most emotionally affecting is the ambush scene. The scene switches from light-hearted and playful to terrifying and deeply distressing, as various characters including those played by Clive Owen, Julianne Moore, and Chiwetel Ejiofor are attacked by an armed gang.
The scene itself is incredibly complicated, requiring amazing co-ordination. For a start, there's the burning car that blocks their path, then there's the motorcycle chase, the bullet which strikes Julianne Moore's character and the violent encounter with the police. Supposedly, Cuaron actually thought filming of the scene had been spoiled when some blood splattered against the camera lens, but he was convinced by cinematographer Emmanuel Lubezki to leave it in, and the single take was saved.