The series 'IT: Welcome to Derry' has provided an explanation for why Pennywise remains in Derry. However, details about the storyline and Pennywise's actions are still unfolding, with some episodes raising questions about the character's actions and the show's possible exploration of time travel. The show's creators have taken a approach to withholding information about Pennywise, which may be contributing to the series' scare factor.