Here's 15 times that actors in the Marvel Cinematic Universe broke Marvel Studios' strict rules to prevent spoilers. Over the last eleven years, the MCU has become the biggest ongoing movie franchise, and one of the most popular of all time. This can be directly seen with the box office haul of Avengers: Endgame, which is currently the second highest-grossing movie ever, and is a direct result of the fans that it has accumulated.

These fans are not only passionate about the MCU, but many also want to be surprised by what the movies contain. Marvel Studios has a knack for being able to do just that, and this is partially because they normally do a great job of protecting spoiler-filled details from surfacing before they want to. This is especially true when it comes to Avengers: Infinity War and Avengers: Endgame, where fake scripts were given to actors, and marketing footage changed to keep certain details about the films under wraps.

Related: What The New Avengers Lineup Looks Like After Endgame

Keeping these secrets has become more difficult though, with cast members like Mark Ruffalo and Tom Holland having a tendency to reveal info, but they aren't the only ones. In Screen Rant's newest video, we take a look at 15 times when MCU actors broke any of Marvel's rules and ended up spoiling something, or just doing something they weren't supposed to. Both Ruffalo and Holland have a few instances mentioned in the video, so check the full list in the video at the top of this post.

Avengers Endgame Poster Cropped MCU

Ruffalo and Holland have had some major slip ups - like Ruffalo live-streaming the first ten minutes of Thor: Ragnarok during the premiere, or Holland accidentally spoiling the ending of Avengers: Infinity War to a crowd who was about to see the film for the first time - but Marvel's also done a great job of using Holland's spoiler tendencies to their advantage. He "leaked" the first poster for Avengers: Infinity War and the title of Spider-Man: Far From Home on social media, making him a great marketing tool for Marvel and Sony.

The most recent examples of Marvel actors breaking these rules though don't have to deal with them, as it was Chris Pratt who opened up the floodgates on videos and photos from the top secret set of Avengers: Endgame. Robert Downey Jr., Chris Evans, and Elizabeth Olsen have each shared videos of the cast on set together, and the rest of the cast continues to share their own now that the film has been out in theaters for a few weeks. They weren't supposed to be documenting anything from the set initially, so at least they've all protected the spoiler-filled photos and videos from leaking before now.

MORE: Endgame Directors Answer Fans' 15 Biggest Questions

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