The spider wasn’t itsy-bitsy and neither were Sydney Sweeney’s screams after she was bitten in a rom-com scene gone wrong. (Watch the video below.)

The actor showed the outtake from “Anyone But You” on “The Tonight Show” Tuesday, proving that arachnids make the worst co-stars.

Sweeney said she was told the spider “was trained.”

“I don’t know how you train a friggin’ spider,” she noted to host Jimmy Fallon.

Sweeney’s fears were confirmed when the spider bit her for real during a scene with co-star Glen Powell in which she is supposed to scream for comic effect. Instead, she let out the blood-curdling variety.

“They thought I was making really serious dramatic choices in a rom-com,” she said. “Glen [Powell] was the only one who was like, whoa, I think this is a little real.”

Fallon then screened the outtake with Sweeney’ erupting into “It’s biting me, it’s biting me, no, it’s really biting me!”

“It got you?” Powell asked as the crew gathered around.

“That was a soul scream,” Powell told Fallon. “I thought I was gonna die.”

The arachnid actor, who deserves a talking-to by its agent, was a Huntsman spider, which is venomous but generally not enough to harm humans.

Sweeney then showed the lighter take that made it into the movie.

“Anyone But You” opens Dec. 22.

Fast forward to 5:10 for the spider drama: