More than half a million people around the world have seen the theatre show, and yet its secrets remain exactly that. Which in a world where spoilers from shows like Game of Thrones litter the internet within minutes of it airing, is an impressive feat.

"Nobody's spoiled the secret, nobody's said what happens, nobody kind of discloses the secrets of Ghost Stories which means that when audiences come in they have absolutely no idea what to expect," says director Jennifer Sarah Dean.

"People have been so good at keeping the secret and I think it's because they go and they have this incredible experience, they don't want to ruin that for other people."

Written by the Jeremy Dyson (The League of Gentleman) and Andy Nyman (star of Death at a Funeral), Ghost Stories combines live theatre with the thrills of a great horror film - but is completely blood and gore free.

"The first time I saw Ghost Stories was actually when it was in the West End in London, and I had absolutely no idea what to expect except I'd seen the trailers and I'd seen posters and I'd been told it's very scary," Dean says.

"I walked in there going, 'this isn't gonna scare me, I know all about theatre, I'll be fine'. Walked in, the first time they started playing the music, I actually screamed, and from that moment I was absolutely gripped.

"It's just the biggest rollercoaster of a play and it just grabs you from the second that you walk into the space, til the moment that you leave again. And you kind of leave and catch your breath again and go, 'oh my gosh, that was incredible and incredibly intense and incredibly exciting and I want to see that again'."

The show even comes with a disclaimer, warning pregnant women, people under 13 and anyone 'with a nervous disposition' to steer clear.

In this day and age of desensitisation, Dean says a stage show needs to be very clever to scare the living daylights out of a live audience.

"It comes down to a really really clever script, and the writers, they're masters of their craft. They're massive horror fans themselves and they've put so much intricate detail into this script and looking at what scares people and also different ways in creating fear and how we look at fear and all these kind of things - they're so clever.

"And that's really the great thing about the script for me - every single word has been so precisely written to take you on this journey and I think the fact that you never know where it's gonna go."

For some, the scares are too much, with people in shows in London and Sydney walking out in as little as five minutes. But others seem to not be able to get enough.

"I know our producer Peter when he first saw the show in London, I think he saw it four or five times, and a lot of people go back, it really is one of the incredible things," Dean says.

"Without giving too much away - there's a little bit of a psychological element to it that people often don't expect, and so as well as it being those big jump moments and those kind of scares, there's a little bit of a psychological undertone which encourages you to come back again and again to see the little bits you missed and work out how it all fits together."

Other than the West End in London, Ghost Stories has only visited Sydney, Toronto and Moscow, and this year's visit to Australia will be its first real tour, with shows in Geelong, Adelaide, Melbourne, Wagga Wagga, Canberra and Perth.

While it's a niche genre, Dean's career has included multiple forays into horror, and she counts herself as a fan of giving scares and being on the receiving end.

"I don't know what it is. I guess it started from being a kid and just absolutely loving watching movies where your heart's beating and you're just on the edge of your seat and you're completely gripped," she says.

"I think that feeling of complete engagement and immersion in the world is what's so exciting. And I've been really lucky, I did a whole lot of horror-related installation events and murder mysteries and scare attractions back in the UK and it's just incredible finding the different ways you can scare people and also finding the audiences who want to be scared. People are queueing up to experience that."

A search of the Ghost Stories website is filled with videos from during the show, with the cameras facing the audience instead of the stage. Person after person is shown screaming, covering their eyes, grabbing their neighbour and recoiling at whatever is going on on stage. So if watching it that traumatic, why would you want to go?

"As much as we hate to be scared, there's something that we love about it as well, from the moment when you're a baby and they play peek a boo with you it's at that kind of fear of the unknown that we kind of crave.

"People love it, they love to be scared, and I think I feel like that as well, there's something as a creative, being able to make people laugh is incredible, getting that real kind of buzz and satisfaction with that. But being able to make people scream, I dunno, it's on a whole new level, it's so exciting."

Ghost Stories is on at Canberra Theatre Centre August 17-21. Tickets $59 from canberratheatrecentre.com.au.