Townsville is getting an extra dose of girl power.

On Sept. 17, the Powerpuff Girls are adding to their ranks, EW can exclusive reveal. Long a trio (Buttercup, Blossom, and Bubbles), the Powerpuff Girls are getting an all-new fourth member.

Image zoom Cartoon Network

Cartoon Network will unveil the as-yet-unnamed fourth Powerpuff girl in the premiere episode of the five-part movie event, The Powerpuff Girls: Power of Four, airing Sunday, Sept. 17 at 5:30 p.m. ET.

While the network has revealed the new superhero’s silhouette, the full identity of the latest member of the crime-fighting trio (now quartet) will be revealed on air.

As with most Powerpuff Girls plots, the super-powered, genetically modified trio must unite to battle the forces of evil threatening the city of Townsville, only this time they have some extra help in their fight against evil.

Check back here as the episode airs for more information on this exciting new character.