Considering just how fast news spreads on social media, it's a miracle Ruffalo's interview slip didn't go viral.

[Editor’s Note: Spoilers for “Avengers: Infinity War” follow]

“Avengers: Infinity War” was one of the most top secret productions in Hollywood, with a majority of cast members not even receiving the full script so that there would be no risk of spoilers going public. However, it turns out Mark Ruffalo shared perhaps the biggest spoiler about the “Infinity War” ending while sitting down for a television interview with “Good Morning America” in July 2017 (via ScreenCrush). Ruffalo’s spoiler didn’t go viral, which is something of a miracle for Marvel fans.

Ruffalo was joined by Don Cheadle during the interview, which took place before the release of “Thor: Ragnarok.” When asked whether Hulk and Thor save Asgard in the “Thor” sequel, Ruffalo mentioned, “Like every other Marvel superhero movie, it doesn’t end well for the superheroes.”

The moderator mentioned that “someone always bites the dust” in Marvel movies, to which Ruffalo replied: “Wait until you see this next one, everybody dies!” The “next one” refers to “Infinity War.” As anyone who saw the tentpole over its record-breaking opening weekend knows, the film concludes with Thanos succeeding in wiping out half of the universe’s population. Avengers that die include Black Panther, Scarlet Witch, Star Lord, Spider-Man, Falcon, and the Winter Solider, among many others.

“Good Morning America” posted Ruffalo’s reveal on Twitter in July 2017, but the spoiler never caught on with fans. Many of the responses believed Ruffalo’s comment was fake because Marvel would never allow “GMA” to post the video if it were true. Disney owns both Marvel and “GMA’s” parent company, ABC.

The video is still up and running on the official “GMA” twitter page. Don Cheadle’s “oh my god, what did you just do?” expression is worth seeing for yourself. “Infinity War” is now playing in theaters nationwide.

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