It's almost Halloween, which means it's time for Ellen DeGeneres to start pranking celebs left and right! Today's victim? None other than Hollywood hunk Jake Gyllenhaal.

Taylor Swift's ex appeared on the show to discuss his new thriller, 'Nightcrawler,' but instead ended up getting spooked himself, thanks to a guy with a seriously creepy doll mask who jumped out and scared the stuffing outta Jake.

Here's how it went down:

Jake Gyllenhaal was merely responding to a question about why he's drawn to dark movies when out popped the most terrifying man-dressed-as-a-little-girl-doll you ever did see, causing the actor to scream bloody murder.

"Oh my God!" he yells, visibly taken aback, as the audience shrieks with delight. "What the f---?!"

LOL! Watch Jake Gyllenhaal's hilarious reaction in the video clip above. We can't stop laughing! (Sorry, Jake.)

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