As I was writing 'Insidious 3' I started to fall in love with the characters and the story. I became very possessive of it and I didn't want someone else to do it.

The good thing with 'Insidious' and 'The Further' is that it's so nebulous, this supernatural world, that it allows you to bend things. There's a lot of room, it's very malleable, like how in the second film we had a lot of time travel.

That's one of the great things about creativity. You labor away in a room, and when you're writing a film, it couldn't be more of a solitary activity or a lonelier job, but if you then write a film that gets made and goes out into the world, it kind of flies away from you. It's not yours anymore.

Freddie Kruger, Jason, Michael Myers - they're all our generation. I think the kids wanted some new guys that they could take ownership of and Jigsaw was that guy.

I love, and I've always loved, contained sci-fi films that utilize practical effects. I feel like the human eye can tell when something is actually in the frame and when it was inserted digitally later.