IT: Welcome to Derry Episode 4 is set to release on November 16, 2025. HBO confirmed it will air on their channel and be available to stream on Max. The series takes place in Derry in 1962 and continues to expand the Stephen King universe, exploring the town’s dark past and the terrifying presence of Pennywise.
The fourth episode is called The Great Swirling Apparatus of Our Planet’s Function. It marks the midpoint of Season 1. The show has already built a strong following with its slow-building tension, eerie atmosphere, and nostalgic nods to King’s wider world.
Episode 4 will air on HBO at its usual Sunday slot and be available on Max shortly after. International viewers can watch through local HBO partners. In the UK, the episode is expected to air on Sky Atlantic and stream on NOW. Each episode of the series releases weekly on Sundays, giving fans a consistent schedule. The Season 1 rollout is:
Episode 1: The Pilot – October 26
Episode 2: The Thing in the Dark – November 2
Episode 3: Now You See It – November 9
Episode 4: The Great Swirling Apparatus of Our Planet’s Function – November 16
Episode 5: Nebloit Street – November 23
Episode 6: In the Name of the Father – November 30
Episode 7: TBA – December 7
Episode 8: TBA – December 14
A preview from HBO hints at tense moments in Episode 4. Chris Chalk’s Dick Hallorann appears in an interrogation room, warning a tribal member that what’s coming won’t be pleasant. Another scene shows Matilda Lawler’s Marge speaking to General Shaw, played by James Remar. Marge mentions being followed by the same person behind Teddy, Phil, and Susie’s deaths. These scenes suggest the episode will dive deeper into Derry’s mysteries and growing unrest.
Fans also expect more hints about Pennywise’s origins, based on glimpses from the preview. U.S. viewers can watch on HBO or stream on Max, while UK fans can tune in via Sky Atlantic or NOW. The episode will roll out globally through HBO’s distribution partners.