10 Horror Movie Scenes More Real Than You Think

10. It Chapter 2 - Jessica Chastain Felt Like She Was Drowning In Blood

Despite being A-list actors working on the sequel to one of the most successful horror movies ever made, the adult cast of IT: Chapter 2 were still put in sticky situations. James McAvoy in particular injured himself doing his own stunts, and took months to fully heal after production wrapped.

One difficult scene to film you might not know was actually shot for real though, comes in a sequence where Jessica Chastain's Beverly is nearly drowned in a pool of blood. As the bathroom she's in quickly fills with the red stuff, Bev struggles to avoid going under.

Now, you might have assumed this was simply filmed in a pool with the water's colour being changed via CGI in post-production, however the effect was actually achieved in camera with 5,000 gallons of fake blood.

As Chastain recalled, the sequence was rehearsed with regular water, but the eventual substance substituted for blood was much thicker, more difficult to act in and, of course, impossible to see through if she became submerged.

Fortunately, the actress was never in real danger, but she did say Bev's desperation in the film reflected her own while filming, as she struggled with the rising liquid and worried that nobody would know if something went wrong.