Mark Ruffalo has a reputation for spoiling "Avengers" plots. You know it. He knows it. So he had some fun with it.

While on "The Tonight Show Starring Jimmy Fallon," The Hulk actor "spoiled" the "Avengers 4" title -- insisting the news was already out there.

The show bleeped Ruffalo out, going with the gag that it was a huge spoiler:

He was almost certainly just joking around. But you never know. So fans got to work analyzing what was bleeped. This fan came up with "The Last Avenger."

Was it just a play on "The Last Jedi"? Will the title in fact be "The Last Avenger" -- as a bookend to "Captain America: The First Avenger"? A new title rumor floating around suggested it's "Avengers: Annihilation." There was early talk that it was "Infinity Gauntlet" before that was shot down. We were pretty fond of the idea that it was "Avengers: End Game," but the title is supposedly NOT said in "Avengers: Infinity War," which would rule out "End Game."

All of this is probably low-key irritating Marvel Studios boss Kevin Feige. He seems to think the "Avengers 4" title build-up has gotten out of hand. It was never meant to be this deep. But fans caring too much about your studio's movie is an excellent problem to have.

Joe and Anthony Russo directed both "Avengers: Infinity War" and "Avengers 4: Whatever They Call It." They responded to Mark Ruffalo's title spoiler as part of this cheeky exchange:

Haha. The sad part of that joke is that Ruffalo may actually be done with his job as Bruce Banner/The Hulk. No firing necessary. So many changes are ahead in "Avengers 4," including a goodbye for Chris Evans as Captain America. Chris Hemsworth also said his contract as Thor was ending with "Avengers 4."

The original Avengers are stepping out of the spotlight. So Ruffalo being "fired" may just be a joke, but his Hulk may indeed take that "final exit" hobo walk off the screen.

"Avengers 4" is currently scheduled to open in the U.S. on May 3, 2019. The title should be officially announced any time now...

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