Warning: This article contains spoilers for Insidious: The Red Door. Insidious: The Red Door boasts many returning characters from the Insidious franchise. One of the strengths of the popular horror film series has been its dependable cast, which comes back in one capacity or another in every installment. Insidious began with Josh (Patrick Wilson) and Renai (Rose Byrne) Lambert engaging psychic Elise Rainier (Lin Shaye) to examine their comatose son Dalton (Ty Simpkins), who was being stalked by malevolent entities from a dimension called The Further. The family continued to be terrorized in Insidious: Chapter 2, but two later sequels, Insidious: Chapter 3 and Insidious: The Last Key, focused primarily on exploring Elise's paranormal origins and other world-building.

https://screenrant.com/insidious-red-door-returning-characters/