Like many things in life, when creating a movie it's important to start off on the right foot.
If you stick the landing, fans will happily buckle up for the rest of the exciting ride to come. However, if you c*ck up the opening to your feature then there's a good chance you'll be fighting an uphill battle with spectators for the next two hours or so.
What turns a fairly mediocre first scene into a truly mesmerising one, though?
Well, more often that not, completely shocking an audience by giving them a moment or exchange they definitely weren't expecting so early in the film tends to do the trick and shatters any other expectations they had for the experience as a whole going in.
Killing off seemingly vital characters within minutes, instantly throwing the main antagonist into a blistering action sequence or even just the sight of visual effects which didn't even seem possible at the time, have all well and truly caught audiences entirely off-guard over the years.
So prepare to pick your jaw back up off the floor as we take a look at ten films which set the tone for things to come in the most stunning way imaginable... and yes, there will be spoilers.
10. Law Abiding Citizen - Clyde Shelton's Family Is Killed
Law Abiding Citizen (2009) instantly lets you know that you're in for a seriously intense and often unpredictable two hours with its absolutely horrific opening scene.
After engineer Clyde Shelton (Gerard Butler) is seen interacting with his young daughter and applauding her necklace making efforts, he is asked to answer the door by his wife and the entire scenario is suddenly flipped on its head.
Shelton is quickly hit in the head with a baseball bat and two intruders break into the house. Shelton then has his hands tied behind his back and is stabbed in the stomach, before being forced to witness the same thing happen to his wife. His daughter is then taken away by one of the men (Christian Stolte) and Shelton loses consciousness.
Though we don't actually see the murders on screen and only find out later that both Shelton's wife and daughter were killed in the home invasion, this scene left audiences in a state of complete shock and let them know this feature wasn't going to go the way they were perhaps expecting.
It also made us thoroughly understand exactly why Shelton goes to the lengths he does throughout the film to seek justice for the heartbreaking death of his family.