Judy Greer was "truly terrified" the first time she saw Michael Myers on set.

The 46-year-old actress - who is reprising her role as Karen Nelson in upcoming sequel 'Halloween Kills' - has revealed her first impression when she saw James Jude Courtney in character as the iconic horror movie villain in 2018's 'Halloween'.

She told SFX magazine: "That was legit scary to me, the first time I saw him in the dark. We were shooting a scene in the house in the woods and I saw him and I was truly terrified.

"James, who played him mostly in our first movie, is very tall and very scary-looking. Not his face, just when he has the mask on. [laughs]"

"If Michael Myers came up to me at my own house, I would freak out, probably pee my pants."

Despite the legitimate fear, Greer revealed how much fun the cast had on set.

She added: "Even when we're shooting the intense, we're still laughing and having fun. [laughs] It's weird how fun making a horror movie is, it's as fun as making a comedy.

"It's just a little bit more exhausting because you have to shoot at night. I guess people expect this to be dramatic. But actually the subject matter is traumatic, but the experience is quite liberating. And so ridiculous."

She admitted there was something "weirdly freeing" about letting loose.

She said: "It's fun to run around and scream, it's really weirdly freeing. But you have to really get into screaming and you have to let go.

"It can be very vulnerable when you're just in front of a bunch of strangers screaming, you kind of have to get that, it's weird.

"Because it seems like it wouldn't be a big deal, but it is strange."