Avengers: Endgame includes a cleverly hidden Easter egg related to the backstory of Black Widow (Scarlet Johansson) and her background as a ballet dancer. Black Widow's origin story has factored into her arc in the Marvel Cinematic Universe, and while it has minimal importance to the plot of Endgame, the movie does feature a reference to Natasha's early life.

Marvel's former Soviet super spy has played crucial roles in a total of seven movies in the MCU, beginning with Iron Man 2. In the last nine years, Black Widow has wrestled with her past and her association with USSR, fought side-by-side with Captain America, helped save the world from Ultron and Loki, and witnessed the snap that wiped out half the universe. Avengers: Endgame brings Black Widow's story to a close when Natasha and Clint (Jeremy Renner) go on a mission to find the Soul Stone. To give the Avengers a chance to undo the snap, Natasha doesn't hesitate to make the ultimate sacrifice. Black Widow's story is over, but a solo movie in 2020 will explore an adventure that precedes Avengers: Infinity War.

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A scene from Avengers: Endgame set at Avengers HQ depicts Black Widow's office, where a pair of ballet shoes can be spotted for just an instant. The shoes are, of course, a reference to Black Widow's origin story, and possibly an indication that Black Widow is still holding on to a piece of her childhood. In the comics, Black Widow has a background in the ballet. Prior to her marriage to the Red Guardian, Natasha was involved in the USSR's "Black Widow" program where she was trained as an assassin. She developed a career as a successful ballerina, and was implanted with memories of being taught ballet at a theatre in Moscow.

Black Widow in Avengers Endgame

Based on what's been seen so far, Black Widow's MCU counterpart has a similar past. Her past comes back to haunt her in Avengers: Age of Ultron, when she's forced to relive the memories of her time at the Red Room Academy. Training for the girls at the Red Room Academy included ballet dance lessons.

This is something that may be revisited in Marvel's Black Widow movie. Though its setting, which is between Captain America: Civil War and Infinity War, is decades after her training, the film could use flashbacks and characters associated with her origin to dive into her checkered past. Encounters with her comic book husband Red Guardian (David Harbour) and fellow Black Widow Yelena Belova (Florence Pugh) could allow audiences to gain an even better understanding of how Natasha became the Black Widow.

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