For a horror movie that clocks in under two hours, Insidious: The Red Door does pack a lot in, especially since it ties all the loose ends left from previous films in the franchise. For instance, moviegoers see the aftermath that becomes the family's lives due to the events of Insidious: Chapter 2, which not only emphasizes how much they have endured and can overcome in the last decade but also highlights the traumatic scars the Lamberts carried. Moreover, it shows the unintended (but highly significant) consequences inadvertently caused by Elise Rainier (Lin Shaye) in Insidious: The Last Key, particularly her part in the storyline surrounding the iconic red door. Nevertheless, there's still an unresolved issue because of how the new installment plays out.
Source：https://www.cbr.com/insidious-the-red-door-conclude-lamberts-story/
