Jimmy Fallon Straps Mark Ruffalo to Lie Detector Machine to Get 'Avengers' Spoilers Out of Him

While most of the cast-members of the "Avengers" franchise know how to keep a secret, there are one or two -- well, there are two -- loose lips that Marvel has been struggling with for awhile.

And while Tom Holland has become the poster child for blurting out what he shouldn't while doing press for his various Spider-Man projects, let's never forget the O.G. spoiler king, Mark Ruffalo. The Incredible Hulk has gotten himself into trouble on more than one occasion, and Jimmy Fallon was determined to get him in trouble again.

It wouldn't be the first time, either, as Ruffalo got himself into a lot of hot water the last time he dropped by "The Tonight Show" last year and tried not to spoil anything.

"Yeah, I got in a lot of trouble. Yeah, I did," Ruffalo said. "And you thought it was funny, hahaha. Next thing I know, Joe Russo has fired me on Twitter."

Ruffalo tried to solve his problems this time by suggesting that he do his press tour alongside Holland. "I love that guy," he said. "I'm gonna put him in front of me. He's like a human spoiler shield."

Well, Fallon wasn't going to let that stop him from trying to get some spoilers, so after the commercial break he strapped Ruffalo to a lie detector machine to see if he could get him to reveal any spoilers even if he did manage to say nothing.

"What kind of questions are you gonna ask me?" Ruffalo lamented as Fallon strapped him in. "I don't want to get fired."

Fallon then proceeded to ask him a series of surprisingly relevant questions, with Ruffalo refusing to answer them. Nevertheless, the machine had plenty to say.

"Is the Hulk secretly a shape-shifting alien known as a Skrull?" Fallon asked. Ruffalo complained he couldn't answer that, but the machine lit up. So what was the lie? Or was it just stress? Was Fallon on to something?

He asked about hidden clues in the latest trailer, who was sexier in the cast and even asked if Bruce Banner and Black Widow (Scarlett Johansson) were finally going to get together.

"Jimmy, I can't!" Ruffalo said, but the machine had plenty to say.

""I'm gonna take that as something," Fallon said.

But then the whole bit ended with a surprise twist that has us wondering what, if any of it, was real. Were those real clues for "Avengers: Endgame"? Or was the whole thing an elaborate game on us?

We only have to wait until April 26, when "Avengers: Endgame" finally hits theaters nationwide.

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