When “Fear Street” writer-director Leigh Janiak recruited Christopher Allen Nelson as special makeup FX designer and department head for Netflix’s trilogy based on the R.L. Stine books, she knew she had the right person to pay homage to ’90s slasher flicks such as “Scream.”

Janiak’s goal was that the “skull mask” killer in the first installment, “Fear Street: 1994,” should be “iconic.” Nelson, a horror veteran and Oscar winner for “Suicide Squad,” cites classic horror films like “Friday the 13th” and “Halloween,” noting the simplicity of the masks.

“I wanted this to look familiar, as if it were something you bought from a Halloween store,” says the FX designer, who also created special makeup effects for the 2018 “Halloween” and for another Stine adaptation, “Goosebumps.”

He went through numerous iterations in designing the skull mask, starting with concept art before experimenting with different shapes and sizes of skulls. “I realized the more complicated I tried to make it, the further away I got from the point.”

As he worked, he also had to consider the actor — making sure there was room to breathe, see and emote through the latex. He created at least 15 variations for the film. “Skull mask is a Halloween mask. It’s a latex mask.”

For Nightwing, Nelson found the creation challenging to create a burlap mask. “He thought, ‘Wouldn’t it be good if it looked like someone who put a cellophane mask over their head and they’re trying to breathe and it molds to their face.” The mask was made from burlap and foam latex.

Janiak had never made a horror film before, it was her first foray into the genre. She explains continuity was key when it came to the masks. “I had to think about the movie magic of it all and that the actors could see through the masks. But continuity was a huge part of continuity – if we shot for 12 hours, he had to make different masks that reflected the different stages.”

She calls those little details that she had not thought about until collaborating with Nelson.

The three-part series, coming July 2, gets its “creepy and scary” feel from the combination of makeup, effects and costumes. Janiak hopes despite its R rated that an 11-year-old or 12-year-old could sneak into it and “not be so scared that you never want to leave your room again.”

Nelson teases, “This is more than a guy-in-a-mask movie.”