A major spoiler for the Black Widow standalone movie was recently revealed. Robert Downey Jr. will most likely have a cameo in the movie in his iconic MCU role of Tony Stark. But don't start celebrating just yet. It is very likely the cameo will simply be unused footage from Captain America: Civil War rather than any new scenes.

The MCU has been notoriously gun-shy when it comes to giving the only female founding Avenger her own standalone movie. Even Captain Marvel got her own movie before Widow, along with having the MCU's general storyline retroactively changed to reveal she had been the inspiration behind the creation of the Avengers team by Nick Fury.

Meanwhile, Black Widow was routinely lost in the hoi-polloi of her overly muscled teammates with magical hammers and cutting edge body armors. With only her wits and a sweet scissor kick at her disposal, it was long believed that heroes like Black Widow and Hawkeye were good for a teamup movie, but not interesting enough to get their own solo film.

Related: Endgame Statue Honoring Black Widow's Sacrifice Leaves Marvel Fans Perplexed

But almost a decade after the character's introduction, and after she has already passed away in the current MCU timeline, the Black Widow origin film will finally give us a glimpse into the backstory of the character that led her from her life as a Russian spy to becoming a part of the Avengers.

As is common in Marvel films, the Iron Man cameo is probably designed to give a friendly boost to the movie and attract more fans to the theaters, a lot of whom would willingly watch an entire movie about Widow just for a few minutes of Iron Man screentime.

But with Robert Downey Jr.'s contract at Marvel up, it seems the filmmakers have hit upon a way to use his character without actually having to re-hire him. A large chunk of the Black Widow movie will reportedly take place during the events of Civil War, when Natasha betrayed Tony to help Cap.

It is reportedly this juncture of Natasha and Tony's relationship that the new movie will refer to, by using some of the previously unused footage from Civil War where Tony confronts Nat about her betrayal. It's not the cameo that fans were hoping for, but it's better than having Natasha meet Tony in the current timeline and reveal that both heroes had survived their Avengers: Endgame demise because they had been Skrulls all along or something.

This isn't the first time the MCU is planning to use old footage instead of filming a new scene. As revealed by Kevin Feige, before Stan Lee passed away, he filmed a bunch of cameos in a number of different settings. And these bits of reserve footage will be used in future Marvel films, to continue the tradition of a Lee cameo in every Marvel movie even after the legendary comic-book creator's death. This news comes from ComicBook.com.

Neeraj Chand