A 'Black Widow' solo movie could finally be on the way after Jac Schaeffer was hired as the screenwriter.

Scarlett Johansson as Black Widow

Scarlett Johansson as Black Widow

Scarlett Johansson has starred as Natasha Romanoff's alter ego in the Marvel Cinematic Universe - including appearances in the likes of 'Iron Man 2' and 'Captain America: Winter Soldier' - but a stand-alone blockbuster has never been confirmed.

However, as reported by The Wrap, 'Blacklist' screenwriter Schaeffer has been hired by Marvel to work on a script, suggesting it could eventually become a reality.

While Scarlett's contract was due to expire after 'Avengers 4' - which will hit the big screen in 2019 - it is said she may have signed an extension to continue playing the former spy.

The 33-year-old actress has appeared as the character seven times to date, but as the money-spinning franchise looks towards its Post-Phase Three - which includes all the movies made after 'Avengers 4' - Scarlett has admitted to having mixed feelings.

Speaking recently on the set of the fourth 'Avengers' film, she said: "It's bittersweet to imagine not having these films to come back to. I've been living this story with these people for 10 years through ups and downs. We've built a great family. Personally, it feels like a loss."

Despite having mixed feelings, Scarlett feels excited about the future of the Marvel Cinematic Universe.

She explained: "It's very surreal for me to watch these new cast members come in and get their feet wet and breath new life into these characters who are so iconic. I feel a lot of joy for the next generation.

"It's a bittersweet feeling but overall it's a positive one. I feel good about the work we've done and the work I've done."