'We have unfinished business': Marvel Studios surprises with teaser to 'Black Widow' film

Marvel Studios just dropped the eagerly anticipated teaser trailer to "Black Widow," the standalone adventure of Scarlett Johansson's super spy-turned-Avenger.

Her character sacrificed her life to help save half of humanity during "Avengers: Endgame," but "Black Widow" takes place years before -- between the events of "Captain America: Civil War" and "Avengers: Infinity War."

As any fan of the Marvel Cinematic Universe could tell you, the Avengers were fractured: Captain America was on the run and several of his team members were under house arrest for violating the Sokovia Accords.

"Black Widow" centers on what Natasha Romanoff was up to at the time: evidently, the ex-KGB agent reunites with some of her former comrades, fellow assassins from the "Black Widow program" that spawned an army of highly-trained agents like her.

"I'm done running from my past," she tells William Hurt, reprising his role as General-turned-Secretary of State Thaddeus “Thunderbolt” Ross.

Among this "family" to which Natasha returns are Florence Pugh's Yelena Belova and Rachel Weisz' Melina Vostokoff. "What brings you home?" Pugh asks her "sis" after the pair get reacquainted with each other at gun and knife-point.

"We have unfinished business," Nat replies.

The family reunion also includes David Harbour's Alexei Shostakov/The Red Guardian, the one-time USSR equivalent of Captain America, but now out of shape and more than slightly worse for wear. It looks like the "Stranger Things" star had a blast playing him.

"AH! Still fits!" he boasts about his more than snug superhero gear. "You got fat," Weisz's character jabs.

The family reunion apparently has the team taking on an army of baddies and the villain Taskmaster, who, according to Marvel lore, has the ability to mimic any fighting style he observes.

"One thing's for sure -- it's gonna be a hell of a reunion," Romanoff promises.

Harbour told ABC Audio that the movie was "surprising" to him and he couldn't praise Aussie director Cate Shortland enough.

Shortland is the first female to direct a Marvel film on her own. "Captain Marvel," the first standalone female-fronted Marvel Studios film, was co-directed by Anna Boden and Ryan Fleck.

Harbour said of Shortland, "She's phenomenal and ... funny, and sort of a rich human being. I feel like I'm very, very lucky to be a part of it."

He went on, “I think it's really cool. And it's also very surprising. I mean you, go into these meetings thinking a certain thing or having an idea in your head ... and then [Shortland] very much surprised me with what they wanted to do with this particular movie and what she wanted me to do. It was very surprising."

"Black Widow" opens May 1, 2020.

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