Marvel Studios has finally given viewers their first glimpse of the MCU's Phase 4, with an action-packed trailer for Black Widow, which shows Natasha Romanoff in two distinct new costumes. The film presents a previously untold story set in the aftermath of Captain America: Civil War, with Natasha Romanoff being one of the world's most wanted criminals after she betrayed Team Tony. One theory is that the different outfit is from Romanoff's past: Black Widow's new costume could really be the outfit she wore when she worked for the Red Room.

The Black Widow trailer confirms that this movie will include at least one flashback scene, with one shot showing a de-aged William Hurt reprising the role of Thunderbolt Ross. Interestingly, Marvel has used their famous CGI technology to make him look even younger than he did in his MCU debut in The Incredible Hulk; this suggests this scene may be set decades ago, earlier in Ross' career than has ever been seen before.

Related: Black Widow Trailer Proves The Movie Is Years Too Late

But this raises an interesting question: if there is one flashback, could there be others? The key to identifying potential flashback scenes would simply be to look for individual shots that don't join up organically with the main narrative, and one is immediately visible.

Black Widow's "New" Costume Doesn't Make Narrative Sense

Black Widow Poster D23

The Black Widow trailer shows Natasha Romanoff wearing two distinctive costumes. The first is a white version of her usual outfit, and it makes perfect narrative sense. The second, however, is rather more unusual. It's a dark bodysuit that was originally unveiled in a poster distributed at D23, looking more like armor than Romanoff's usual outfits, and with what may well be the straps of a detachable parachute at the back. While the full costume isn't visible in the Black Widow trailer, the D23 poster confirms that it features a wealth of weapons: Romanoff is wearing a version of her traditional "Widow's Bite" gauntlets, she's carrying her staves, and she has guns strapped to her legs. Interestingly, the costume also includes a Black Widow logo on the belt.

But where would Romanoff get this costume from? It's important to remember that Black Widow is set at a time in the character's life when she was operating without her usual resources. SHIELD has been rendered defunct, and the Avengers have been shattered after the passing of the Sokovia Accords. Indeed, that may be why Natasha is forced to seek out old allies — Yelena Belova, Melina, and the Red Guardian — for help. However, there's no evidence these three would have the equipment to create a custom bodysuit like this for Black Widow.

The shot of Black Widow in the poster shows her with a different hairstyle, one that hasn't been seen before in the MCU and isn't present in the trailer, either. This, naturally, raises the possibility that this shot is from another flashback scene. If that's the case, this could actually be the uniform Romanoff wore back when she used to work for the Red Room; rather than a new costume, this is really her first one. Supporting this theory, the Black Widow trailer also shows one brief glimpse of Rachel Weisz's Melina wearing the same outfit, and she's confirmed as a Black Widow as well.

Related: MCU Theory: How Black Widow Reunites With The Avengers

Is This How Black Widow Wound Up On SHIELD's Radar?

Thunderbolt Ross Black Widow

There appear to be structural similarities between Black Widow and Captain Marvel, with both serving as unorthodox origin stories. Thus Black Widow sees Natasha Romanoff forced to go back to her beginnings, and it's most likely she's attempting to take down the organization that trained her in the first place. Thus, it's reasonable to assume any flashbacks are important parts of Black Widow's backstory, and that they tie together somehow.

The costume shot seems to show Black Widow in front of a crashed plane; it's possible the straps over her chest were previously attached to a parachute. If that's the case, then Marvel's Black Widow: Deadly Origin miniseries may provide an important clue, because that comic began with Natasha Romanoff stealing aboard an experimental fighter jet. In the series, her mission went wrong and the plane crashed. Black Widow: Deadly Origin has proved to be an influential comic for the MCU's portrayal of Black Widow, and Natasha's solo movie is already confirmed to draw upon it substantially; this was the miniseries that introduced Black Widow's white costume.

It's easy to miss, but in the background of the costume shot there are military vehicles rushing to the scene of the crash — cars identical to the one in the shot featuring General Ross. In the MCU, Ross was heavily involved in super-soldier experiments and attempts to develop enhanced technology; it's not hard to imagine a scenario where he'd been working on an experimental jet at some point in his career. The vans behind Ross are labeled in what appears to be Hungarian; the United States has always had a strong relationship with Hungary, and in the 1990s established several air bases there. In the MCU, one of these air bases could have been used to quietly test an experimental jet the American government didn't want the world to know about just yet — one that Natasha Romanoff attempted to steal.

All this is only theoretical, of course, but it certainly does make sense. According to The Avengers, at some point Natasha Romanoff wound up on SHIELD's radar in the worst possible way. Fortunately for Black Widow, SHIELD sent Hawkeye to assassinate her, and Clint Barton made a very different call. A recent MCU timeline dated Natasha's switching sides as happening in 1997, which would be right about when the United States was operating air bases in Hungary. The details match up surprisingly well, definitely supporting the idea that these Black Widow flashbacks reveal just how the assassin and super-spy Black Widow found her way into SHIELD.

More: Black Widow Trailer Breakdown: 23 Story Details & Secrets You Missed

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