Warning: This article contains spoilers for Insidious: The Red Door. As Insidious: The Red Door proves, it wouldn't be an Insidious movie without the return of psychic paranormal expert Elise Rainier. Lin Shaye once again portrays the medium with close ties to the Lambert Family for the fifth installment in the franchise, which takes place ten years after the events of Insidious and Insidious: Chapter 2. Elise also appeared in Insidious: Chapter 3 and Insidious: The Lost Key, both of which added more backstory to her character and expanded on the world-building and lore of the franchise by showing aspects of her childhood and spectral experience prior to meeting the Lamberts.
In Insidious 5, Josh (Patrick Wilson) and Renai (Rose Byrne) are separated, Josh's mother (and Elise's old friend) Lorraine (Barbara Hershey) has died, and Dalton (Ty Simpkins) is heading off to college. Elise's old colleague Carl has suppressed Josh and Dalton's memories about astral projection and The Further, but circumstances conspire to draw them back into the dark world of the Lipstick-Face Demon and his malevolent minions once Dalton draws the Red Door in art class and Josh stumbles upon troubling family history. What follows is the return of the Lambert family curse and a need for Elise's guiding light in the darkness once again.
Elise Returns As A Ghost In Insidious: The Red Door's Ending
Given when the movie takes place, Elise can only appear at the end of Insidious: The Red Door as a ghost. She's already been dead over a decade after Josh strangled her when he was possessed by the Black Bride at the end of Insidious. Regardless of the circumstances of her demise, she still cares about what happens to the Lambert family, and just as she's presented herself to help them before in spectral form, presents herself to Josh after he's closed the Red Door to The Further.
Even though Josh doesn't recognize her, Elise consoles him with the knowledge that he'll be able to tell Lorraine all about what he's been through later, and that for the present he should "keep a steady stride," something she often told people entering The Further. This implies that she might be able to instruct him in ways to reach loved ones who have crossed over into an incorporeal plane of existence. That way, his astral projection won't just be associated with horrible demons and traumatic experiences.
When Elise's Video Takes Place In The Insidious Timeline
Prior to Elise popping up as an apparition, she appears in a video that Chris shows Dalton when they're researching his ability to explore The Further. In the clip, she tells a group of individuals about what The Further is, the sorts of tormented souls that are tapped within it, and why they're drawn to any of the living who cross over into their realm. It's a good way to introduce exposition for the characters without being too long-winded and retread scenes already seen by the audience in the other movies.
As far as the timeline of Insidious movies is concerned, this video takes place prior to the events concerning the Lamberts, somewhere after Insidious: The Lost Key and before Insidious: Chapter 3. It's a fun way to connect Elise to the franchise in a way that makes sense for the plot. As she's emerged as a central and iconic figure throughout the series, it further highlights that there are numerous ways for her to appear in future spin-offs even if the Lambert family horror has now come full circle with Insidious: The Red Door.