WARNING: The following article contains spoilers for Avengers: Endgame, in theaters now.

The Marvel Cinematic Universe has depicted a number of deaths over the years, although none carried the impact as half the heroes -- and, indeed, half of all life in the universe -- turning to dust in 2018's Avengers: Infinity War. But while those losses are reversed in Avengers: Endgame, as expected, some heroes don't survive the blockbuster sequel.

One death hits particularly hard, as, unlike, say, Tony Stark or Steve Rogers, the character's fate hadn't been the subject of intense speculation in the lead-up to Endgame's release. Nevertheless, the loss of Scarlett Johansson's Black Widow completes a character arc that began in 2010, and advances the film's story.

The New Nick Fury

During the five-year time jump after the climax of Infinity War, Black Widow becomes one of the only Avengers still actively helping the world. Operating out of the New Avengers Facility, Natasha Romanoff is reintroduced communicating with allies like Captain Marvel and Okyoe and coordinating their missions. With half the population gone, she's more or less become the new Nick Fury. But, really, was there anything else Natasha could have become?

Unlike the other Avengers, her growth has centered around her shifting morality. She's abandoned her mercenary attitude for a more heroic core. She used to do good things only when it was requested by someone she trusted, but now she's the leader, doing good in a world that needs goodness. She even tells Steve Rogers, "This job, this family ... I'm better because of it." She doesn't have a family to go back to like Tony Stark, or vengeance to fuel her like Clint Barton. She isn't trying to fix herself like Bruce Bruce, and she hasn't given up like Thor and Steve have. She's become too heroic to really stop being a hero, and that's how she redirects her pain. Her transition makes her arguably the most effective of the Avengers, and the only one who still wants to be a hero. Therefore, a purely heroic death is incredibly fitting.

Widow's Wail

When the heroes decide to use the Quantum Realm to try and recover the Infinity Stones, Black Widow and Ronin (née Hawkeye) are sent to the planet Volmir for the Soul Stone. Learning that a sacrifice is required for the Stone to materialize, Clint and Natasha each volunteers. It quickly turns into a literal fight each tries to be the first to leap off the cliff. Whereas Thanos had to hurl Gamora to her death, Clint and Natasha do everything they can to prevent the other from making the leap. However, in the end, it's Natasha who takes the leap.

Make no mistake, Natasha doesn't have a death wish. Clint clearly wants to sacrifice himself to help bring back his family, and to atone for his years spent as Ronin, killing criminals. But Natasha is no longer atoning for the red in her ledger, as referenced in 2012's The Avengers. She's simply being a hero, and sacrificing herself for the sake of her friend. It's a major loss, no doubt, but it also earns the Soul Stone, and helps to save the universe.

A Hero's Death

Natasha spent much of her time in the MCU with a flexible moral code. She was willing to risk the lives of others to accomplish her mission. But being a hero changed her. It made her more willing and able to recognize when it was time to do something destructive but heroic, as Captain America described in the original Avengers as "lying down on the wire" so someone else could survive. It's a knowing sacrifice that completes Black Widow's arc. But that doesn't make it any less surprising or heartbreaking when it happens.

Of all the original Avengers, none were as unsentimental as Black Widow. She was loyal to only handful of people (notably Nick Fury and Hawkeye), but that was it. However, as she formed relationships with heroes, she became one herself. Her death feels necessary but not inevitable; it was a choice she had to make.

Directed by Joe and Anthony Russo, Avengers: Endgame stars Robert Downey Jr. as Iron Man, Chris Evans as Captain America, Mark Ruffalo as Bruce Banner, Chris Hemsworth as Thor, Scarlett Johansson as Black Widow, Jeremy Renner as Hawkeye, Brie Larson as Captain Marvel, Paul Rudd as Ant-Man, Don Cheadle as War Machine, Karen Gillan as Nebula, Danai Gurira as Okoye and Bradley Cooper as Rocket, with Gwyneth Paltrow Pepper Potts, Jon Favreau as Happy Hogan, Benedict Wong as Wong, Tessa Thompson as Valkyrie and Josh Brolin as Thanos.