Over the course of nineteen films, Marvel Studios has yet to give a female hero top billing. That changes with the release of this week's Ant-Man and the Wasp, which will see Evangeline Lilly's Wasp get top billing as she makes her Marvel Cinematic Universe debut. So, how does a studio like Marvel Studios inform an actress that their character will be named in the title? Through e-mail, of course.

In a new interview with The Hollywood Reporter, Lilly recalled how she initially found out she'd get to suit up as the Wasp, and how the studio informed her of the sequel's title. Like most new franchises, Ant-Man wasn't guaranteed to be a success -- especially given all the behind-the-scenes drama that took place ahead of production -- but that hadn't stopped Marvel Studios from thinking ahead of what could be. As Lilly recalls, upon being cast in the first film, she knew that she'd get to suit up as the Wasp should a sequel happen, which led to the actress becoming quite invested in the box office success of Ant-Man. However, while she knew Hope would get her own suit in a sequel, she didn't know that the Wasp would get equal billing with Ant-Man until she received a surprise e-mail with the sequel's title card.

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When they cast me in the first Ant-Man, I knew that if the first film was a box-office success, then that would mean I would get to put on a suit. So there was probably no one more invested in the box office numbers of Ant-Man than me. Once the film was successful enough to warrant a second, and I knew that that was going, I still didn't know that Wasp would be getting equal billing with Ant-Man. So that came as a surprise later: I got a surprise email with nothing but a JPEG of the title card. And that was how they told me. Pretty cool.

While it's not the first female-led film from Marvel Studios -- that title goes to 2019's Captain Marvel -- it is a small step forward for superhero films, as female heroes are finally getting their due on the big screen following the massive success of Wonder Woman.

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Opening Friday nationwide, director Peyton Reed’s Ant-Man and The Wasp stars Paul Rudd, Evangeline Lilly, Bobby Cannavale, Michael Peña, Tip “T.I.” Harris, Judy Greer, David Dastmalchian, Michael Douglas, Michelle Pfeiffer, Laurence Fishburne, Hannah John-Kamen, Randall Park and Walton Goggins.