Fake blood can be sticky, messy, and well, a bit gross, but when acting in a horror film, wholly necessary.

We caught up with Emma Roberts, Kiernan Shipka, and Lucy Boynton to talk about their new film, The Blackcoat's Daughter, and the good amount of fake blood that comes with it.

"It's fun until it starts getting sticky," said Shipka. "We were having a conversation in the makeup room, 'Do you want it more like a veiny purpley, blue how viscous do you want it,'" added Boynton, which evoked a shudder and an "ugh" from Roberts.

The movie, without giving too much away, centers around two girls left at a boarding school during winter break, and a mysterious young woman, traveling to said boarding school with the help of a couple dealing with a death in their family. 

"I was so enthralled with the script," said Shipka. "I just thought it was such a simple quiet movie but at the same time so complex, and that's what I loved about it, these different layers." Roberts agreed, saying "this is much more than a horror movie, which I liked. Reading the script, it read to me like a novel."

Boynton studied up for the movie by watching classic horror movies like Rosemary's Baby, Don't Look Now, and The Shining. "I have a really great respect now for those kind of classic horror films that like this are much more than horror and trauma, it's more the human story behind that."

Watch the full video above to see what the girls thought of the filming experience and how they prepared to go seriously dark in The Blackcoat's Daughter, in select theaters and on demand starting today, March 31.