Zero

Priya's erratic behavior begins because she becomes possessed by Lilith, a biblical demon. The possession manifests gradually through sleepwalking, memory gaps (like the lipstick incident), and increasingly disturbing actions. Her family history of mental illness initially makes everyone believe she's experiencing similar symptoms, but the truth is a supernatural entity controlling her body.

The lipstick theft she cannot remember foreshadows the loss of her own agency as Lilith takes control.

Lilith is a biblical demon created before Eve, born from Adam in ancient mythology. She rebelled against Adam and was cursed with childlessness by God. Over centuries, she conceived repeatedly with the Devil's offspring, but most children died or were stillborn. Priya is the only child who escaped death, making her the perfect vessel for Lilith's return and her mission to destroy the world.

The film's opening creation myth establishes Lilith's origins before the human drama begins.

The Devil, appearing as a snake, sends Lilith to possess Priya as part of an apocalyptic mission to destroy the world. Priya being the only surviving child of Lilith's bloodline makes her the ideal vessel for the demon. The Devil tasks Lilith with fulfilling this destructive plan, using the centuries-old grudge between Lilith and humanity as leverage.

The opening creation prologue foreshadows the cosmic battle between divine and demonic forces.

When Lilith tries to choke Bala, physical contact between them triggers a powerful reaction. Because Bala and Priya are soulmates connected through seven births, their bond is strong enough to momentarily override Lilith's control. This contact restores Priya's memories of their life together, allowing her to briefly reclaim her body before Lilith's possession resumes.

Solomon explains earlier that the seven-birth soulmate bond gives Bala unique power against Lilith.

God intervenes when Lilith's possession threatens to destroy the world. He freezes time to stop the demonic takeover and reveals that Bala and Priya were chosen to be the parents of His child, a divine purpose that makes their union cosmically significant. The pregnancy serves as both a blessing and a permanent seal against Lilith's destruction, fulfilling a larger celestial plan.

The creation prologue establishes divine involvement in human destiny from the start.

Three professional exorcists from different parts of the world attempt to remove Lilith but fail because the demon's power is too great. Lilith has existed for millennia and possesses immense strength from her ancient origins. Only the combined intervention of divine power and the sacred soulmate bond between Bala and Priya proves capable of defeating her.

Solomon warns early on that this is no ordinary possession but a demonic entity of biblical proportions.

The ending shows the Devil, still in snake form, transforming back into a towering human figure and vowing to complete his mission alone. This establishes that while Lilith has been defeated and the immediate threat is over, the cosmic battle is far from finished. The post-credits tease directly hints at a sequel titled Zero-2, suggesting the Devil will continue pursuing his apocalyptic goal through new means.

The divine intervention stops Lilith but does not eliminate the Devil himself.

Priya's mother went mad during pregnancy and died giving birth to Priya, creating a family history of mental illness that initially explains Priya's strange behavior to others. However, this is revealed to be a red herring, the true cause is supernatural possession by Lilith, not inherited mental instability. The parallel between mother and daughter serves to mislead characters and viewers alike.

Bala's father's disapproval of the marriage stems from this family history, adding realistic doubt to the supernatural explanation.

Priya takes lipstick from a store but has no memory of doing so, causing a confrontation with a security guard. This incident marks the first sign that Priya is losing control of her own actions. It foreshadows the larger theme of possession where her body acts independently of her will, and it serves as an early clue that something supernatural is affecting her mind and behavior.

Later, in her dream state, Priya recounts being branded a thief by others, connecting this incident to her deeper psychological trauma.