The "Captain America: Civil War" flick is being touted as the darkest one of the series and fans could have the radiant Scarlett Johansson to thank for it all.

Yahoo reports Johansson is set to reprise her role as the Black Widow, sharing the screen with co-stars Robert Downey Jr., who plays Tony Stark and Iron Man, and Chris Evans, who is Captain America.

In anticipation of it all, she recently teased the website, "As the scope of these movies is larger and larger and the danger kind of looms larger and larger, I don't want to say that the film has a darker tone, but the film has a darker tone and I think it's maturing along with the fans."

"The Avengers" was the fastest film to pass the $1 billion mark in box office earnings when it was released three years ago and to hear Johansson rave the sequel set to be released early next month will be even more action packed.

Pregnant throughout much of "Avengers: Age of Ultron's" production, Johansson said she felt an even more emotional connection to her character this time after its revealed she was forcibly sterilized.

"When you have something (and) you can imagine not having it, I think it added a different kind of dynamic that I would never have expected, but it was certainly helpful, yes," she said.

Johansson also hints she gets a high from the idea of transforming a powerful female character from a fictional, comic book character to one live and active on the big screen.

"There have been unbelievably powerful female characters in the comics for decades and decades, so it's always on our minds," she recently told E! Online.

"Age of Ultron" finds Tony Stark frantically trying to get a peacekeeping program off the ground, only to be stymied in his efforts by a villain's counterplan to destroy all of humanity.