Insidious, the 2010 horror movie from director James Wan, made almost $100 million and has spawned a trilogy of films. But, the original was shot with a budget of just $1.5 million and produced in just three weeks! That’s just one of the facts packed into the latest episode of You Think You Know Movies, which takes a trip into The Further with Insidious!

Wan, who went on to direct Furious 7, and writer Leigh Whannel both worked together previously on the very first Saw film. If you look closely in one of the scenes, you can see a drawing of Billy, the Jigsaw puppet from the Saw franchise, drawn on the blackboard in Patrick Wilson’s classroom. Just a little easter egg for all you horror fans.

“You Think You Know Movies?” is a ScreenCrush original series that dives deep into the cinematic worlds of your favorite movies and freeze frames a few tidbits you might not have known. We’ve already tackled Star WarsThe Avengers and Spider-Man, but now, it’s time to travel to the astral plane with Insidious!

Watch more installments of ‘You Think You Know Movies?’ below and let us know what movies we should cover next.

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