Warning: This post contains Black Widow spoilers.

In Marvel's Black Widowthe origins of Natasha Romanoff's family have a connection to the Winter Soldier program, making Bucky Barnes' origins as a Soviet assassin that much darker. At the start of the film, Natasha, her sister Yelena, and their two parents were all revealed to be secret Soviet spies, with their family being a cover in order to achieve their mission. Furthermore, the information they stole was directly connected to the Winter Soldier, revealing that Bucky was used and experimented on in all sorts of ways that ended up creating even more of a dark legacy than originally thought.

As the first act of Marvel's Black Widow reveals, Natasha's "parents," Melina Vostokoff and Alexei Shostokov, a.k.a. the Red Guardian, were tasked with infiltrating the North Institute, and Natasha and Yelena were brought to help sell the idea that they were all a happy American family, living for three years in Ohio. However, Alexei eventually managed to secure the intelligence they were ordered to retrieve in 1995, and just like that their mission was over. In the aftermath, Natasha and Yelena were sent to General Dreykov's Red Room to be trained as master assassins and spies for the Soviets.

Related: Black Widow’s End-Credits Scene Sets Up Multiple Phase 4 Storylines

Melina confirms later on during the family's reunion in the present day that the intelligence they secured was the collated data, studies, and experiments that had been conducted on the basal ganglia, the part of the brain that deals with a subject's free will. However, she also reveals that this intelligence was created in conjunction with HYDRA's Winter Soldier program, meaning that Bucky was likely experimented on and studied far more than initially believed, seeing as how HYDRA had found great success in turning him into their brainwashed killer. As such, the implication exists that he probably wasn't always put back on ice until his next mission, at least not right away, so that scientists could conduct more studies in an effort to further weaponize the human brain to make more Winter Soldiers. However, Alexei's theft ensured that their work would go to the Red Room instead, serving as the next phase in controlling its Widows.

Blended image of Winter Soldier and Black Widow in the MCU

While Natasha's brutal training and psychological conditioning were more traditional, her sister Yelena Belova's came from this new science and data that had been taken from the Winter Soldier, leading to chemical agents being used that prohibited her and many other Widows from making any of their own choices, being transformed into living and expendable weapons to be activated and deployed as Dreykov saw fit. While this is all serves to make the history and actions of the Red Room completely evil and deplorable, it simultaneously makes Bucky's origins as the Winter Soldier that much darker and tragic than they already were.

While he had no choice, this new part of Bucky's Winter Soldier legacy reveals that the Red Room's second phase of mind-control and manipulations came from experiments on Bucky himself. With Marvel's Falcon & The Winter Soldier having shown Barnes on the road to redemption from his dark past, perhaps he'll join forces with Natasha's family as a result, as they were looking to save all the Widows they could find after the Red Room was destroyed? Whether that happens or not in the MCU's future, the Winter Soldier's connection to the Red Room in Black Widow is incredibly significant.

More: Black Widow: All Easter Eggs, MCU Connections & Hidden Details

Key Release Dates