Imaginary

The movie begins with Jessica (DeWanda Wise) experiencing a horrifying dream where a monster, masquerading as her father Ben (Samuel Salary), transforms into a grotesque spider, but she then awakens from this nightmare in her own bed.

Jessica is celebrated for her "Molli Millipede" children's book series. Her family includes her husband, Max (Tom Payne), and his two daughters, Taylor (Taegen Burns) and Alice (Pyper Braun), with whom Jessica has a mixed relationship; Alice is warm towards her, whereas Taylor displays resentment. The family relocates to the home where Jessica's traumatic childhood events with Ben occurred, events that left her with arm scars.

In their new home, Alice starts conversing with what she claims is an imaginary companion, leading her to discover a teddy bear named Chauncey. Concurrently, Taylor encounters a mysterious woman, Gloria (Betty Buckley), peering at her and later meets a neighborhood boy, Liam (Matthew Sato). An awkward interaction orchestrated by Jessica exacerbates Taylor's frustration, causing her to retreat to her room.

While Jessica and Max view Alice's invisible ally as endearing, Alice remains inseparable from Chauncey. Gloria later introduces herself to Jessica, revealing her past role as Jessica's babysitter, a time Jessica scarcely recalls following her mother's demise.

During the night, Jessica catches Alice engaged in a tea party with her imaginary friend Chauncey. When she overhears Alice complimenting someone on their appearance and a woman's voice expressing gratitude, she's startled to find the woman is Samantha (Alix Angelis), the girls' emotionally unstable mother, who abruptly attacks her. The children intervene to stop Samantha, and following their call, the police and Max arrive. Taylor reveals to her father that she had been in contact with Samantha, hopeful of her recovery. After the ordeal, Jessica tucks Alice into bed, attempting to discuss what happened. However, Alice implies that Chauncey, like a friend Jessica once had, understands her.

With Max away for personal reasons, Jessica is left to care for the children. Alice engages in a treasure hunt orchestrated by Chauncey, while Jessica takes a moment to visit her father Ben in a care facility. Since the traumatic event, Ben's mental health has deteriorated. Despite Jessica's efforts to connect with him, Ben's outburst and forceful grip cause her distress, compelling her to depart.

Taylor has Liam come over, much to Alice's chagrin. Liam presents Taylor with what he claims are drugs, which are later identified as harmless allergy pills belonging to his mother, and he suggests they sneak some of Max's alcohol. When Liam accidentally shatters a bottle, he goes to fetch towels to clean the mess and encounters an eerie presence resembling Chauncey, whose music box tune begins to play as the bear's string extends in the shadows. As the bear draws closer, it transforms into a more sinister version, causing Liam to collapse in terror. Upon discovering Liam, Jessica calls his mother and reprimands Taylor.

Jessica notices that her sketches have been altered, with the characters' heads removed, an act she attributes to Alice. In an attempt to connect with Alice, Jessica speaks to her about her behavioral issues stemming from her mother's situation, drawing parallels with her own past trauma involving her father. During their conversation, Jessica realizes she's actually been interacting with Chauncey under the bed covers, not Alice. Investigating further, Jessica examines the clues from Alice's scavenger hunt, including "something that scares you" (a jar of insects), "something that will get you in trouble" (the snipped drawings), and "something that hurts." She catches Alice about to harm herself with a sharp fence piece, mistaking it for a flower. Jessica intervenes just in time, preventing Alice from serious injury as the nail only grazes her arm.

Seeking professional help, Jessica summons a psychologist, Dr. Soto (Veronica Falcon), to evaluate Alice. During their session, which Dr. Soto documents on video, Alice interacts with Chauncey, who becomes increasingly hostile and derogatorily refers to Jessica as "fake mommy." In a startling moment, Dr. Soto observes that Alice isn't moving her lips while Chauncey's voice is heard. In a subsequent discussion with Jessica, Dr. Soto reveals she saw no teddy bear during the session. When Jessica inquires with Taylor about the bear, Taylor denies seeing it as well. Reviewing the session's recording, Jessica confirms the absence of Chauncey, realizing that only she and Alice can perceive him. Dr. Soto shares another case with Jessica, involving a boy named Luis (Noah Martinez) who, influenced by his own imaginary entity, inflicted severe harm upon himself, echoing Alice's behavior.

Alice vanishes after another interaction with Chauncey, prompting Jessica and Taylor to scour the streets. Taylor holds Jessica accountable for Alice's disappearance, criticizing the upheaval Jessica has caused in their family. Later, Taylor encounters Gloria, who invites her in to unveil Jessica's childhood ordeals. She discloses that Chauncey was Jessica's imaginary companion too, which precipitated a traumatic episode where her father intervened, leading to his breakdown and Jessica's injury.

Delving into her past, Jessica uncovers an old drawing depicting a location she labeled "Never Ever." She revisits the chaotic scribbles she made in her youth within her room, just as Taylor and Gloria come back. They deduce that playing the scavenger hunt is key to unlocking the Never Ever portal. Jessica collects various objects, reaching a point where she needs to find "something that hurts." Consequently, she injures her hand with scissors and places the items in a bowl to ignite them. The portal only activates after Jessica, in a moment of distress, blames Taylor for Alice's disappearance, causing emotional pain for both, which serves as the final catalyst to open the portal.

Entering the Never Ever, a realm shaped by the fantasies of its child denizens, they seek Alice. They encounter a portal reflecting Jessica's traumatic childhood episode. During that night, Ben saved Jessica from the Never Ever, resisting Chauncey's attempts to drag him back. Ben's direct confrontation with the entity's gaze led to his insanity, a sacrifice to protect Jessica from Chauncey's grasp. Meanwhile, Gloria, who has spent years obsessing over the origins of imaginary companions after facing ridicule in her field, seals their exit path, captivated by the realm's potential. However, her fascination is cut short when Chauncey, in his monstrous form, emerges and violently ends Gloria's life.

In a room mirroring their old urban apartment, Jessica and Taylor locate Alice, who is garbed as a princess amidst a sea of gifts, with Samantha also present. They must persuade Alice that the scene is an illusion. Jessica successfully creates an exit, but as they attempt to leave, Chauncey, in a fit of rage and in his monstrous bear guise, targets them. Taylor and Alice escape while Jessica, after a fierce confrontation where she injures Chauncey, narrowly escapes through the portal, reuniting with the girls outside.

Jessica introduces Max and the daughters to Ben, where Taylor expresses regret for her past actions, and Alice affectionately calls Jessica "mom." This moment of warmth is shattered when Jessica discerns they are still within the Never Ever's confines, realizing Chauncey's plan was to lure her back by using Alice. Just as Jessica faces the possibility of eternal captivity, Taylor intervenes. Chauncey, revealing his true monstrous spider form, nearly ensnares Jessica in a fate akin to her father's. However, a quick act by Alice, igniting lighter fluid, engulfs Chauncey in flames, confining him behind the portal as the structure burns down, enabling their escape.

The following day, while attempting to settle into a hotel, the sight of a teddy bear unnerves Jessica, Taylor, and Alice. A young boy claims the bear, mentioning his imaginary friend "Rufus." The camera shifts to reveal the bear, unmistakably the same as Chauncey, hinting at the cycle's ominous continuation.