The cast for HBO Original series “Welcome to Derry” continues to grows larger this week, with Deadline reporting that Rudy Mancuso (The Flash) has been set for a key recurring role.

“Welcome to Derry” is said to include the origin story of Pennywise the Clown, with Bill Skarsgård reprising his role.

“The series will begin in the 1960s in the time leading up to the events of It: Part One, the 2017 film based on the Stephen King horror novel. The story is also said to include the origin story of Pennywise the Clown.”

Andy Muschietti and Barbara Muschietti and Jason Fuchs are on board the Pennywise prequel project from Warner Bros. Television, with Muschietti set to direct several episodes.

The series hails from a story by Andy Muschietti, Barbara Muschietti, and Fuchs based on King’s novel It. Andy Muschietti and Barbara Muschietti executive produce through their Double Dream production company alongside Fuchs, Brad Caleb Kane, David Coatsworth, Skarsgård, Shelley Meals, Lee and Lin. Fuchs, who wrote the teleplay for the first episode, and Kane serve as co-showrunners.

Published in 1986, Stephen King’s massive novel was of course first turned into a mini-series in 1990, with Tim Curry playing the role later played by Bill Skarsgård in the movies.

The tale centers on the town of Derry, Maine, where a group of friends called the Losers’ Club battle Pennywise the killer clown first as kids, and then 27 years later as adults.

Mancuso joins already announced cast members Alixandra Fuchs (Hatfields & McCoys), Kimberly Guerrero (The English), Dorian Grey (Transplant, Star Trek: Discovery), Thomas Mitchell (Gangland Undercover, Spiral), BJ Harrison (Family Law, Maid), Peter Outerbridge (Batwoman, Saw VI), Shane Marriott (Fargo, Law & Order Toronto: Criminal Intent), Chad Rook (Joe Pickett, Billy the Kid), Joshua Odjick (Little Bird, Wildhood) and Morningstar Angeline (Echo, Westworld), Taylour Paige (Zola), Jovan Adepo (“Watchmen”), Chris Chalk (“Perry Mason”), James Remar (Oppenheimer), Madeleine Stowe (Revenge) and Stephen Rider (Daredevil).

The series will air on HBO in addition to streaming on Max.

“Welcome to Derry” is expected to arrive in 2025.