It's only a tiny spoiler to say that even Mysterio himself doesn't love the gold-plated, caped costume he sports in Marvel's new sequel, Spider-Man: Far From Home.
"I didn't know how much I was gonna love it," Gyllenhaal told Yahoo Entertainment during a recent stop into our Los Angeles studios. "I fell deeply in love with that suit. The other day we put it back on for some press stuff we were doing and, oh, the sweet feeling of tight spandex."
The 38-year-old actor must have not gotten the memo that as an actor in the Marvel Cinematic Universe, you're supposed to complain about what they make you wear, not extol it.
He will admit it was cumbersome, though: "It is [heavy]. The chest plate itself attaches to these metal prongs that I have to put on, and the cape attaches to that. And then inevitably there are these electric drills that they have to drill into the chest plate. And it's a full wool cape, like proper Game of Thrones times four, with light battery packs. And a number of people, when they're walking behind you, do [step on it]. It's like wearing a ball gown. You're all the sudden choked by [it]."
Another thing Gyllenhaal loved about his Spidey experience: Spidey himself, Tom Holland.
" I just love him, he's a good dude," said the actor, who almost played Peter Parker himself 15 years ago when Tobey Maguire was injured prior to filming 2004's Spider-Man II.
"There's an appropriate amount of adoration on both sides. He has a tremendous amount of experience in this world, and with the character, he's so fantastic in it. I have such respect for him as Spider-Man and all the work he does. And also a real respect for his work ethic.
"In the opposite way he's seen work I've done and has really admired it, and has the appropriate amount of deference for the narcissistic ego of an actor, being me. And so that made a nice balance."
That's not to say the self-deprecating Gyllenhaal didn't enjoy taking the piss out of the 23-year-old Brit.
"I constantly do things to antagonize him. It's great fun. Just physically, like scaring him. Just frightening him," he laughed.
Spider-Man: Far From Home is now in theaters.
Watch Jake Gyllenhaal talk about almost playing Spider-Man:
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