WARNING: The following article contains spoilers for Marvel's Black Widow Prelude #1, by Peter David, Carlos Villa and Chris Sotomayor, on sale now.

In the Marvel Cinematic Universe, one of the best-kept secrets is the background of Natasha Romanoff/Black Widow (Scarlett Johansson). All we know so far is she defected from Russia's Red Room and started working for S.H.I.E.L.D. as a spy for Nick Fury. While her upcoming solo movie is expected to provide more insight into her history in Russia and how her past was truly shaped, Marvel's Black Widow: Prelude #1 has revealed key insight into her origin and why she became a hero.

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The story, the first of two chapters, opens up right after the Civil War movie with General Ross discussing the events of The Winter Soldier with Councilwoman Hawley, who is on the U.S. Security Council. They were Fury's bosses, and we jump back to when Widow impersonated Hawley to stop Alexander Pearce killing his colleagues. Ross is grateful for her services but after she flipped on him and allowed Team Cap to escape, Ross wants her brought in as she has a lot of secrets belonging to the government.

Hawley laughs it off, though, as she doesn't think it's necessary. Widow saved their lives, after all. But also, she thinks bringing in such a super-spy is impossible. When she asks Ross about Widow's past, he details how a Russian military boss, General Dreykov, brought her into the fold as a promising youngster, which Madame B weaponized in the Red Room. When they get into how she defected, however, Ross presents a Rashomon-esque sequence with a few options in the field of battle.

While he doesn't know the truth, Ross says one account is she ran into Hawkeye on a mission gone wrong and he saved her life. Not seeing her as an enemy but a victim, he bonded with Nat and turned her, similar to what he did with Scarlet Witch. This may well be the Budapest assignment we heard so much about, and it seems they were on opposing sides, only to make amends. The other account is Widow actually saved Fury's life in a similar scenario, and he offered her a chance to work by his side, impressed by her skills.

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Lastly, Ross believes it's the "ceremony" that could well have tipped her allegiance. This was the procedure we learned of in Age of Ultron that resulted in her losing the ability to have children. She even tried to throw fights in the Red Room so she wouldn't have to endure this, but Madame B saw right through her efforts. The flashbacks show her crying and not wanting to undergo the surgery, but nonetheless it was carried out for Nat to graduate. But the indoctrination wasn't as perfect as thought. Ross indicates she seemingly switched teams on her own, actively seeking out S.H.I.E.L.D., as it might have been the only way to survive betraying the Russians. So as heroic as she was, it could have been a move in the name of self-interest as harming Nat would result in war between world powers.

What Ross does know is, after this, she got shot by the Winter Soldier, as she told Steve Rogers. Natasha was then put on babysitting duty in Iron Man 2. There, she kept watch over Tony Stark for Fury. Right now, the exact reasons Natasha switched sides is unclear. However, the tie-in comic still does provide some clarity, as the "ceremony" seems to be the breaking point for Natasha.

Directed by Cate Shortland, Black Widow stars Scarlett Johansson as Natasha, Florence Pugh stars as Yelena, David Harbour as Alexei aka The Red Guardian and Rachel Weisz as Melina. The film opens on May 1, 2020.

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