The MCU Still Hasn't Explained Black Widow's Last Mystery

Following what is likely the character's final appearance in Black Widow, the MCU has still not explained Natasha Romanoff's last mystery from Captain America: Civil War. As a world class spy with a complicated past, Natasha had many secrets, some of which were eventually answered in her solo Black Widow movie in 2021, like how she first became a black widow assassin. Yet, other secrets she seemingly took with her to her grave.

Her supporting roles in many other Marvel movies over the years provided bits and pieces of Natasha's backstory, like when she and Hawkeye discussed their time together in Budapest during the first Avengers, or when Natasha opened up to Steve Rogers in Captain America: Winter Soldier. Although Civil War primarily focused on Tony Stark's crumbling relationship with Rogers, they weren't the only Avengers drudging up the past. Natasha in particular delivered a throwaway line to the Winter Soldier that sparked many questions from viewers eager to learn more.

After Bucky Barnes went rogue in Civil War, he briefly fought against Black Widow, who said to him, "You could at least recognize me." The line seemed to hint at some kind of history between the two that has yet to be revealed in the MCU. One theory connects them to their backstories in the comics, wherein Natasha was trained by Bucky in The Red Room, since they were both products of Russia's super-soldier program. The MCU has provided no evidence that their paths crossed during this time, but it is certainly possible that they encountered each other while working for Hydra. Although this explanation does not quite line up with what Black Widow told Steve in Winter Soldier — that the two first met when Bucky killed someone she was protecting — Natasha was a known liar. She might have left out certain details about her past, especially her time in The Red Room, because she felt no need to reopen old wounds or possibly even cause her friends to view her differently.

Then again, Black Widow's quip to Bucky in Civil War could have just as easily been a reference to the encounter that she mentioned to Steve. Despite the ambiguity of her words, she might have simply meant, "You could at least recognize me from when you nearly killed me a few years ago." Natasha also could've been referring to their more recent face-off in Winter Soldier, sarcastically implying Bucky was being rude for not remembering their last fight against each other. The MCU loves inserting funny jokes into even the most serious story moments to add a bit of brevity, so it's entirely possible that Natasha's remark in this scene held no deeper meaning at all. Her tendency to rely on deception to maneuver out of difficult situations means Natasha might have just been lying. In the heat of the moment, she could've been trying to get Bucky to question his jumbled memories enough that she could gain the upper hand in their fight by implying they shared a history, when in fact they did not.

Although Black Widow sought to further flesh out Natasha's character and explore her backstory, there was only so much a single movie could cover. Unfortunately, her sacrifice in Avengers: Endgame makes it unlikely that the MCU will dive much deeper into her past, leaving certain mysteries forever unsolved. Viewers will have to be content with their own theories surrounding Natasha and Bucky's relationship in Captain America: Civil War and beyond.

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