Top 10 Most Important Details in the Background of MCU Scenes

“Iron Man” (2008) & “Iron Man 2” (2010)
Three years before Captain America was introduced to the MCU, we got the first glimpse of his signature weapon. When Pepper walks in on Tony taking off the Iron Man suit, a prototype shield can be spotted in the background. Then, in “Iron Man 2,” the shield gets more attention—though not the respect it deserves. Since Cap’s shield was frozen in snow, this isn’t THE shield, but it still establishes a connection. Seeing the weapon in Tony’s workshop hinted at his family’s link to Captain America. That connection was later confirmed when we learned his father designed the original shield in the first “Captain America''. Across various films, Tony’s relationship to the weapon would go on to be a significant plot point.

“Avengers: Endgame” (2019)
There were many recognizable faces from the superhero community at Tony Stark’s funeral. But it wasn't immediately clear who the young man standing alone was supposed to be. We later discovered that the mystery mourner was Harley Keener. When Tony was struggling in “Iron Man 3”, Harley helped him get back on his feet with some supplies and a few important words. The billionaire repaid the boy’s kindness with a garage of gifts. Although we hadn’t seen Harley since that movie, his quiet cameo in “Endgame” proved that he likely remained close with Tony. It’s unclear whether Harley’s appearance is foreshadowing a bigger role. Either way, his presence served as a subtle reminder of Iron Man’s positive influence—both universally and on a more personal level.

“Thor: The Dark World” (2013)
While Erik Selvig is in a mental institution, he tries to teach the residents about planetary alignment. If you look closely at a chalkboard, you'll notice that he's written that all the realms exist within the “616” universe. The small detail comes back in a big way during “Spider-Man: Far From Home”. When Mysterio is explaining the concept of multiple worlds, he says the MCU’s earth is in dimension 616. Although he was lying about many things, he wasn’t wrong about the multiverse. “Avengers: Endgame” confirmed that multiple realities exist. Maybe Mysterio got his information from Selvig’s research! Even if the good doctor didn’t give the villain his backstory, Selvig knew about earth’s place in the multiverse before most Avengers did.

“The Avengers” (2012)
During a tense conversation between Loki and Thor in “The Avengers”, two ravens fly onto the scene. These weren’t just any birds. Odin has a pair of ravens that he seems very attached to in the MCU. Within Norse legends, his birds could observe distant lands and return to give him information. It’s safe to assume that Odin relied on them to watch over his two sons whenever they traveled. There’s even a possibility Loki was aware of the ravens we missed. After all, is it just a coincidence that he calls Thor “Odinson” in a bitter tone right after the birds arrive? Whether Loki knew the ravens were there or not, their observations likely helped motivate Odin’s decision to imprison his adopted son.

“Captain America: The First Avenger” (2011)
When we saw Red Skull pop up in “Avengers: Infinity War,” our jaws collectively dropped. But this event was actually foreshadowed in an extremely subtle manner way back in the first “Captain America”. Near the end of the film, it appeared Red Skull had been disintegrated by the tesseract. But as we later learned, the Space Stone inside the cube allows you to teleport wherever you wish. The major background detail that confirms Red Skull was teleported instead of disintegrated back then are the stars that appear above his head. At the time, we all just thought it was a bizarre, if beautiful tesseract side effect. But that small detail paved the way for one of the most shocking MCU moments—Red Skull on planet Vormir.

“Avengers: Age of Ultron” (2015)
After his rather creepy introduction, Ultron sends multiple Iron Man drones to attack the Avengers and their allies. But there's one person he chooses to leave alone. When a drone is threatening Dr. Helen Cho, Ultron pauses, turns his head, and calls off the attack. The villain later explains that he spared her so he could use her expertise to build a new body for himself. Considering that Cho’s creation would eventually become Vision, Ultron’s decision not to hurt her was a monumental choice. If he had been a little more reckless in his initial dealings with Cho, we may have had one less Avenger.

“WandaVision” (2021)
At the end of “WandaVision’s” seventh episode, the neighborly Agnes reveals that she’s actually a witch named Agatha Harkness. Although her subsequent musical number shows us a few of the manipulative things she’s done, there are plenty more hints hidden in the series. Agatha tends to pop up when Wanda encounters something that doesn’t belong in Westview. The villain also fails to react to strange things like the twins aging up. But the most hilarious hint that we didn’t catch the first time around was in the sixth episode. During the intro song, she’s wearing pants with the word “naughty” bedazzled onto the back. This fashion choice was her way of letting us know she was up to no good all along.

“Avengers: Age of Ultron” (2015)
The hallucination Wanda gave Thor in “Age of Ultron” predicted the future events of three different films. Heimdall calling the god of thunder a firstborn son and warning about Hel both foreshadowed Odin’s daughter Hela arriving in “Ragnarok”. Thor shooting thunder in the hallucination also references that movie’s best action scene. The split-second glimpse of the infinity stones and Heimdall saying he’s dead both reference the events of “Infinity War.” But the detail you most likely missed is the image that looks like Vision’s eyes opening. Although we definitely didn't understand everything at the time, many things we saw came to pass. For all we know, there may still be something else in the background of that scene that just hasn't happened yet.

“Iron Man 2” (2010)
Wakanda is one of the most beautiful and unique places in the MCU. Add all the advanced tech, and you can understand why government agencies would want to know more about it. Eight years prior to “Black Panther” coming out in theaters, Tony and Fury talked about the Avengers at a S.H.I.E.L.D. facility. If you look at the map behind Tony's head, you'll see a circle around a location in Africa. The highlighted spot looks like it’s where Wakanda would be located on a world map. Wakanda was still keeping its true nature a secret at the time, but S.H.I.E.L.D. appears to have had intel on the mysterious nation long before the rest of us.

“Spider-Man: Far From Home” (2019)
Although Peter and Mysterio formally meet about half an hour into the film, that isn't the first time they've been in the same place. They actually shared the screen twelve minutes earlier. Right before Peter walks into a store in Venice, you can see Mysterio in plain clothes on his phone closely watching Peter. Quentin and his people unleash the “water elemental” on Venice a few minutes later. Was this part of Mysterio’s plan to gain Peter’s trust? Or did he just want to observe Peter in battle before launching his next illusion? No matter what Mysterio’s motives were, seeing him watch Spidey made for a mind-blowing background detail when we finally spotted it.