Geoff Johns, DC Entertainment’s former president and chief creative officer, has announced his first new project — and it’s a return to the very beginning of his career.

Johns announced at San Diego Comic-Con on Thursday that he’s writing and executive producing Stargirl, a new live-action series for DC’s upcoming streaming service, DC Universe. Stargirl is also the first character that Johns ever created for DC Comics; she made her debut in 1999. The series will focus on high schooler Courtney Whitmore, stepdaughter of the Star-Spangled Kid, as she teams up with Justice Society of America to fight a series of DC villains. Greg Berlanti (The Flash, Supergirl, Arrow) will executive produce the series.

The series is extra personal to Johns, according to a report from Deadline. Johns told Deadline the character is based on his sister, who passed away.

“Obviously, Stargirl was first character I created for DC,” Johns told Deadline. “Most important, Courtney Whitmore was inspired by my sister who passed away. To have an opportunity to tell a story celebrating this superhero was literally the first thing I wanted to do because it is so personal to me. Also, a character that speaks to being young, to a legacy and to pushing forward seems so important to me nowadays.”

Stargirl is the fourth live-action series set to debut on DC Universe, alongside the heavily anticipated Titans. The series is set to premiere in 2019, but DC Universe will launch later this year. The streaming service will cost $7.99 a month.