The mythology and chronology of the "Insidious" film series can be a little difficult to follow, and might require a careful walkthrough leading into the forthcoming "Insidious: The Red Door," due in theaters on July 7, 2023.

In James Wan's 2011 original, a married couple named Josh and Renai (Patrick Wilson and Rose Byrne) found their young son Dalton (Ty Simpkins) stalked by scary, supernatural forces. When Dalton falls into a coma, Josh and Renai call in a trio of paranormal investigators in the form of Elsie Rainier (Lin Shaye) and her two nerdy assistants, Specs and Tucker (screenwriter Leigh Whannell and Angus Sampson). Elsie explains that Dalton has the ability to astrally project, sending his disembodied consciousness out into the world while he sleeps. Dalton, however, unwittingly sent his mind into a purgatorial afterlife realm called The Further (the italics are part of the film's established lore). While inside, Dalton attracted the ghosts that live there, and now they're eager to return with him. The ghosts are essentially drawn to Dalton's thoughts, making their presence, well, insidious.

As it so happens, Elsie also knew Josh as a boy, and previously helped him deal with a similar ghostly/astral projection issue when he was being stalked by a wicked ghostly woman. Elsie used hypnosis to repress Josh's memories, lest he accidentally invoke further ghosts. She was ultimately unsuccessful, and a ghost, possessing Josh's body in 2011, kills her.

Josh's repressed memories are a vital part of 2013's "Insidious: Chapter 2," and seem to be the central crux of "The Red Door," a film that catches up with Josh, Renai, and Dalton in the present day. It's been a decade since their first haunting, and the timeline seems to be finally sorting itself out. Let's take a closer look at the newest trailer.

Behind The Red Door

Because Elsie died in the first film, Wan and Whannell had to find clever ways to bring back the film's most exciting character. Portions of "Chapter 2," as a result, take place in 1986, when Josh was a young boy. Thankfully, time has no meaning in The Further, allowing Josh to travel to his own past. "Insidious: Chapter 3," meanwhile, took place in 2007, a few years before the events of the first film, and told the story of how Elsie first began working with Specs and Tucker. "Insidious: The Last Key" ties events to the 1950s in flashbacks, but then fast-forwards to 2010, immediately before the events of the first film.

"Insidious: The Red Door," directed by Patrick Wilson in his directorial debut, will be the first "Insidious" film since the original to take place in the modern day.

As seen in the new trailer, both Josh and Dalton are struggling with repressed, sometimes-ghostly memories. Neither recalls anything about The Further or their unusual astral projection powers. An astute viewer will likely guess that "The Red Door" will be about how, even after a decade, The Further can still worm its way back into their minds, attracting the usual retinue of ghosts and demons.

Dalton is now old enough to move away to art school (Simpkins is 21), and Renai suggests that Josh drive Dalton to college in an attempt to reconnect after a between-films alienation. It also seems that Dalton's creative process is intense enough to unlock deep wells of ghostliness in his mind, and his etchings will resurrect some familiar faces. Remember the Lipstick-Face Demon from the first film? He'll be back.

Tiptoe Through The Tulips

Elsie may have died a decade before the events of this film, but she will appear, seemingly on an old VHS cassette, to explain certain plot points. It may be a contrived way to resurrect the character, but one must accept any excuse to get Lin Shaye back on camera; her presence and charisma are appreciated. However, Specs and Tucker do not seem to appear in this film, which is a pity.

Props to the music supervisor who selected the 1968 Tiny Tim novelty classic "Tiptoe Through the Tulips" to underscore the preview's scarier moments. Yes, it's a cliché to include lighthearted or upbeat pop music during a film's more harrowing horror scenes, but as this trailer proves, it can still be effective. Let's hope modern kids will discover the glories of Tiny Tim as a result.

Another Familiar Face Returns

The demons and ghosts throughout the "Insidious" movies each seem to operate by slightly different rules. The monstrous Keyface from "The Last Key," for instance, kidnaps souls and locks them up in a spectral prison. The Man Who Can't Breathe from "Chapter 3" encourages people to take their own lives. The Lipstick Face Demon, meanwhile, is a devil keen on bodily possessing the living. Seeing as Lipstick was initially drawn by Dalton's mind, it stands to reason that it will return in "The Red Door" when Dalton's repressed memories resurface.

Even though "The Red Door" is set in the present, it appears to be looking back at the first film more heavily than any of the other sequels. In terms of "Insidious" homework, intimate familiarity with the series' byzantine timeline may not be as important as merely catching up with the 2011 original. This will be, as the chyrons say, about a family's secrets coming to light.

Read this next: 12 Underrated Slasher Movies You Need To Check Out

The post Insidious: The Red Door Trailer Breakdown: Back to the Further One Last Time appeared first on /Film.