Hannah John-Kamen, whose credits include the series Killjoys, as well as episodes of Black Mirror and Game of Thrones, has signed on to be in the Marvel blockbuster as Ghost. In the comics, Ghost is an industrial saboteur for hire who wears a suit of his own design which allows him to become intangible so that he can phase through things, which is a skill the film seems to have kept. As you've probably noticed, the comic book version of Ghost is also male, so clearly Ant-Man And The Wasp is going to reimagine the character a bit. The comic character has also never had his secret identity revealed even though he's been around for 30 years, so it'll be interesting to see if this Ghost has a name or history that we find out about during the course of the film.