Halloween - it's the time when children go out trick or treating for goodies dressed up in frightening masks and costumes.
But it's also the time when adults go to the cinema to watch films which will leave them scared stiff.
The latest instalment of the Halloween films came out earlier this month and became the highest-grossing October movie ever just three days after its release - raking in approximately £60m.
Newsbeat's been looking at what it takes to make a great horror film.
Jamie Lee Curtis in the original Halloween (1978)
Universal's Halloween is the 11th film in the franchise and is the fifth time Jamie Lee Curtis has featured in the Michael Myers saga.
It's an iconic series of films that has made nearly £300m since its first release in 1978 - all by leaving people scared stiff.
Ali Plumb, Radio 1 and 1Xtra's film critic, told Radio 1 Newsbeat the new film is a lot of "fun".
"It's just solid. A good fun night at the cinema - a few scares, a few in-jokes - it works."
Ali says there are three key factors.
Michael Myers returns to Haddonfield, Illinois in Halloween (2018) to find Laurie Strode - played by Jamie Lee Curtis
"To me they've got to have a sense of humour," Ali says.
"They need to be funny because whilst you want to say, 'Oh, that film was really scary' - if there's no light and shade then you can't appreciate the scariness."
Ali says if it's funny and he feels involved with the characters - if he cares whether they do or don't die - then he's in.
We're talking about horror, so it seems pretty obvious to say that there has to be "genuinely scary moments".
But Ali says films also have to be "inventive" with their scariness.
Scream was considered a pretty intelligent, and at times funny, horror movie when it came out in 1996
"It can't just be another mirror scare - where you shut the mirror and turn the camera and boom, there's a cat or whatever. You've got to think more inventively."
The film critic says you have to give the audience something they haven't seen before.
"If this guy is a serial killer, a ghost or whatever, you have to deliver that myth or that story in an interesting way."
Ali says there's an expert use of silence in Halloween and horror films, which means that music and sound effects play a bigger part.
"You might have seen this in IT, where you go - 'Hang on, I can kind of see something' - and then the shape you're looking at turns around.
"That is delivered best when silence and noise is delivered well. It keeps you on your toes."
A burnt serial killer who uses a gloved hand with razors to kill people in their dreams? Yep, that's definitely terrifying
"A big horror icon obviously on a par with the man, the myth, the legend that's Michael Myers, is Freddie Krueger. There's something about The Nightmare on Elm Street series that still stands up.
"There's something about going into someone's dreams and being part of their subconscious that really gets to people - because dreams and the dream world are a state where we are so vulnerable and we don't really know what's going on," Ali says.
"Plus, he's got a terrible jumper and an awful claw - so what's not to love?"