The most epic beatdown at this “Avengers: Endgame” showing didn’t happen on the screen.

A crowd of spoiler-sensitive Marvel fanatics pummelled a loudmouth for yelling out major plot points as they waited to see the blockbuster in a Hong Kong theater, according to reports.

The spoil-sport, who was not identified by name, was leaving one showing of the superhero flick in Causeway Bay, Hong Kong when he started blabbing about key moments to those waiting in line for the next showing, reported Deadline, citing Taiwanese media.

Infuriated movie-goers channeled their inner Hulk, beating up the bean-spilling baddie, reports said.

A purported photo of the aftermath shows a man in a white t-shirt seated against a wall, being treated by a few onlookers as blood trickles down the right side of his face.

The man committed the cardinal cinema sin despite the film’s directors, brothers Anthony and Joseph Russo, requesting on Twitter that fans avoid spoiling the movie for others.

“Because so many of you have invested your time, your hearts, and your souls into these stories, we’re once again asking for your help,” the brothers wrote in the days before the film’s release. “When you see Endgame in the coming weeks, please don’t spoil it for others, the same way you wouldn’t want it spoiled for you.”

“Endgame,” the 22nd movie in the Marvel Cinematic Universe and the final outing for the Avengers, re-wrote the record books in its opening weekend, raking in $1.2 billion worldwide, according to Variety.