Marvel Studios' Black Widow footage has leaked online.

Following the airing of a teaser at D23 Expo, four seconds of Black Widow footage surfaced online. The quick snippet evokes a tone similar to Captain America: The Winter Solider, with grounded action sequences that find Natasha Romanoff fighting for survival.

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The footage is circulating on social media and appears legitimate, though it's possible that it might change before the film's wide-release next year. It is not known at this time when an official teaser or trailer will drop.

The Black Widow film, long rumored to be in production, was officially confirmed at this year's Comic-Con International in San Diego. A teaser trailer also aired during Marvel's Hall H panel. Later, Marvel Studios' Head of Visual Development Andy Park shared concept art of Natasha fighting Taskmaster, the film's villain. The film will be the first to kick off the Marvel Cinematic Universe's Phase 4.

Directed by Cate Shortland, Black Widow stars Scarlett Johansson, David Harbour, Florence Pugh, O-T Fagbenle and Rachel Weisz. The film arrives in theaters on May 1, 2020.

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