New Marvel theory believes that Black Widow played by Scarlett Johansson could be alive and well after the events of Avengers: Endgame in the Marvel Cinematic Universe. The new theory doing the rounds online suggests that the character that died in Avengers: Endgame wasn’t Natasha Romanoff, but her 'sister', Yelena Belova.

Reports state that the character of Yelena will be introduced into the MCU for the first time in the upcoming solo Black Widow film, the release of which was pushed owing to the coronavirus pandemic. The theory, on the other hand, shared on Reddit says that "she used technology that has been established in the series to take on Natasha’s appearance". Photostatic Veils were introduced in the MCU in Captain America: The Winter Soldier, and have been regularly used in the Agents of SHIELD television series as well.

The events of Black Widow take place between the events of Captain America: The Winter Soldier and Captain America: Civil War, thereby making the film a prequel of sorts. For the uninformed, Natasha was killed off in Avengers: Endgame, along with Robert Downey Jr’s Tony Stark.

The film was initially slated for release in April but now has been pushed back indefinitely. Oscar-nominee Florence Pugh will play the role of Yelena and it has been teased by the film’s trailers that both 'sisters' grew up and trained to be Black Widows together. The theory suggests that in Avengers: Infinity War, to acquire the Soul Stone, one was required to sacrifice the soul of someone they love but in Endgame, the rule was changed to simply a soul for a soul, which would ostensibly allow Yelena to fool Red Skull, keeper of the stone.