History Film / InsidIous

** [[spoiler: Chapter 2 shows us who was randomly knocking on the door and how it was left wide open before the family moved as Josh's spirit.]]

** [[spoiler:''The Red Door'' shows that Dalton traveled back in time to the end of ''Chapter 2'' and inadvertently left a conjured hammer from his latest painting that [[StableTimeLoop Parker Crane picked up to attack young Dalton with]]. Adult Dalton runs at Josh and shoves him, exorcising Parker from Josh's body. In the present, the hammer in the painting has vanished.]]

** [[spoiler:''The Red Door'' shows that Dalton traveled back in time to the end of ''Chapter 2'' and inadvertently left a conjured hammer from his latest painting that [[PredestinationParadox Parker Crane picked up to]] attack young Dalton with. Adult Dalton runs at Josh and shoves him, exorcising Parker from Josh's body. In the present, the hammer in the painting has vanished.]]

* CosmicDeadline: ''The Red Door'' finale puts the film into high gear with Dalton being pulled out of his body and into The Further to revisit a key moment from his past and suddenly finds himself captured by Red Face. Josh comes to the rescue almost one queue and Red Face is soon left [[spoiler:trapped behind the Red Door, but not fully defeated]], Renai and Josh part ways on good terms, Elise returns from the beyond the grave again to wish Dalton well, and the film soon concludes.

* NoOntologicalInertia: In ''Chapter 2'', "defeating" the ghost of Parker Crane (essentially like a separate entity) also disables Possessed!Josh until Josh's spirit can return to his body. In a subversion however, ''The Red Door'' reveals that [[spoiler:Adult!Dalton remembered this event through his artwork and revisited it in The Further. He shoved Possessed!Josh to stop him from killing Child!Dalton, forcing Parker Crane out of Josh's body]].

* HyperspaceIsAScaryPlace: The Further is full of tormented and/or malicious dead.

** ''Chapter 3'' shows that possession may grant the victim HealingFactor of all things, which greatly accelerates Quinn's broken bone healing. It isn't clarified if this power is unique to The Man Who Can't Breathe, but given he wants to kill Quinn and is some sort of demon-human, it's quite an unusual power.

* NewPowersAsThePlotDemands: ''Chapter 2'' explains that someone murdered [[spoiler:Elise Ranier]], but it was nobody who was present at the time of death. This is because [[spoiler:Parker Crane was in control of Josh's body at the time of the murder, which altered it in a way that it was as if Parker Crane was there incarnate to do the deed]].

* NewPowersAsThePlotDemands: ''Chapter 2'' explains that someone murdered Elise, but it was nobody who was present at the time of her death. This is because [[spoiler:Parker Crane was in control of Josh's body at the time of the murder, which altered it in a way that it was as if Parker Crane was there incarnate to do the deed]].

* StableTimeLoop: Earlier events can be influenced by The Further existing outside of time and space. This leads to twists like [[spoiler:Josh Lambert "helping" his past self, and Elise and company accidentally leaving a door open that kicks off the events of Chapter 1.]]. ''The Red Door'' reveals that Dalton saved the day from [[spoiler:Possessed!Josh by shoving him and forcing Parker Crane out of Josh's body inadvertently, even saving the life of himself in the past]].

* NoOntologicalInertia: In ''Chapter 2'', "defeating" the ghost of Parker Crane (essentially like a separate entity) also disables Possessed!Josh until Josh's spirit can return to his body. In a subversion however. ''The Red Door'' reveals that [[spoiler:Adult!Dalton remembered this event through his artwork and revisited it in The Further. He shoved Possessed!Josh to stop him from killing Child!Dalton, forcing Parker Crane out of Josh's body]].

* StableTimeLoop: Earlier events can be influenced by The Further existing outside of time and space. This leads to twists like [[spoiler:Josh Lambert "helping" his past self, and Elise and company accidentally leaving a door open that kicks off the events of Chapter 1.]]. ''The Red Door'' reveals that Dalton saved the day from [[spoiler:Possessed!Josh by shoving Parker Crane out of Josh's body, even saving the life of himself in the past]].

* NoOntologicalInertia: In ''Chapter 2'', "defeating" the ghost of Parker Crane (essentially like a separate entity) also disables Possessed!Josh until Josh's spirit can return to his body. ''The Red Door'' reveals that [[spoiler:Adult!Dalton remembered this event and revisited it in The Further to shove Parker Crane out of Josh's body and defend Child!Dalton from dying]].

* NoOntologicalInertia: In ''Chapter 2'', "defeating" the ghost of Parker Crane (essentially like a separate entity) also disables Possessed!Josh until Josh's spirit can return to his body. ''The Red Door'' reveals that [[spoiler: Adult!Dalton remembered this event and revisited it in The Further to shove Parker Crane out of Josh's body and defend Child!Dalton from harm]].

* StableTimeLoop: Earlier events can be influenced by The Further existing outside of time and space. This leads to twists like [[spoiler: Josh Lambert "helping" his past self, and Elise and company accidentally leaving a door open that kicks off the events of Chapter 1.]].

** In ''Chapter 3'', Elise encounters her deceased husband, Jack, in the Further, who tries to persuade her to kill herself so [[TogetherInDeath they can be together again]]. [[spoiler:Elise knows that Jack would ''never'' ask her to do such a thing, revealing that this entity is actually the Bride in Black in disguise.]]

* NoOntologicalInertia: In ''Chapter 2'', "defeating" the ghost of Parker Crane (essentially like a separate entity) also disables Possessed!Josh until Josh's spirit can return to his body. ''The Red Door'' reveals that [[spoiler: Adult!Dalton remembered this event and revisited it in The Further to shove Parker Crane out of Josh's body to defend Child!Dalton]].

* NoOntologicalInertia: In ''Chapter 2'', "defeating" the ghost of Parker Crane (essentially like a separate entity) also disables Possessed!Josh until Josh's spirit can return to his body.

** After Dalton and Josh are hypnotized by Carl into "forgetting" about their astral projection abilities and the related topics, ''The Red Door'' reveals they are both still in danger as before because their astral projection is still activating but their memory suppression just makes dealing with their problems more difficult due to their inability to immediately act from past experience. During the opening of ''The Red Door'', Carl making himself visible to Josh makes Josh wonder if he knows him, which helps start the chain of events.

* NiceJobBreakingItHero: [[spoiler:Josh, instead of fleeing straight back to his physical body, spots the Bride in Black still stalking him and yells at her to leave him alone. This unfortunately only allows the Bride to steal his body and leave Josh's astral body trapped in the Further.]]

* BittersweetEnding: ''The Red Door'' (Chapter 5) sees the door in question sealed up and Elise meets with Josh one last time to wish him well, but the original Lambert family remains apart, their fate left uncertain, and TheStinger reveals that The Red Door, now painted over with black, has a light turn on above it again, implying it may not stay sealed forever.