Zero

Vijay Kumar objects to Priya because of her family's dark medical history. Priya's mother went mad during pregnancy and died giving birth to her. This hereditary mental illness concerns Vijay Kumar greatly, as he fears it could affect his son Bala's future and potentially their potential children.

The film earlier establishes that Priya cannot bear children, which connects to her mother's tragic fate.

Priya takes lipstick from a store without paying and claims she does not remember doing it. This incident is an early sign that Priya is experiencing memory lapses and psychological disturbances, which foreshadow her eventual possession by Lilith. Her subconscious is being manipulated by the demonic entity.

The lipstick theft occurs early in the film, well before Priya's full possession by Lilith becomes apparent.

Lilith targets Priya because Priya is the only child who survived her mother's cursed pregnancy. According to Solomon's explanation, Lilith's curse makes her kill pregnant women and their unborn children. Priya's mother was supposed to die during childbirth, but Priya somehow survived, making her the exception to Lilith's otherwise perfect record of destruction.

Solomon reveals that Priya is uniquely immune to Lilith's curse, which is why the demon fixates on her.

The film explains that Lilith was created before Eve, rebelled against Adam, and was cursed by God with infertility as punishment for her defiance. This curse is central to Lilith's motivation, she desperately wanted children and conceived repeatedly with the devil's offspring, only to watch each child die or be stillborn. This endless cycle of loss turned her into a vengeful spirit who torments pregnant women.

Solomon's revelation about Lilith's origin explains why she fixates on destroying pregnant women and their offspring.

Bala's touch weakens Lilith because their soulmate connection has endured across multiple lifetimes. The film establishes that Bala and Priya are bound by a love that transcends time. This deep bond acts as a counterforce to Lilith's demonic influence, when Bala touches Priya, it triggers her memories and humanity, allowing her to briefly reclaim control of her body from the demon.

The film establishes early on that Bala is determined to stand by Priya despite all obstacles, hinting at their spiritual connection.

God intervenes to freeze time and blesses Priya with pregnancy as divine vindication of her and Bala's unwavering love. Their bond across multiple lifetimes and Bala's devotion despite Priya's condition proved their worthiness. This pregnancy represents a cosmic victory over Lilith, the demon was cursed with infertility, and by giving Priya the ability to conceive, God essentially overturns Lilith's curse and demonstrates her defeat.

Lilith's infertility curse makes the divine pregnancy a direct reversal of her punishment.

After Lilith is destroyed, the Devil appears in snake form and then shifts back to human shape, vowing to complete his mission alone. This ending clearly sets up a sequel (Zero-2) and indicates that while Lilith was defeated, the overarching threat of the Devil remains. The film concludes with the implication that the battle between light and darkness is far from over.

The film establishes early on that the Devil manipulates Lilith's actions as his agent.

The title Zero likely refers to several symbolic meanings: Priya's infertility represents zero chance of pregnancy before divine intervention; she is essentially a 'zero' in Lilith's curse record as the only survivor; and thematically, the couple must face the ultimate void or nothingness before their blessed outcome. The title also hints at the cosmic scale of the conflict involving biblical forces.

The film never explicitly explains the title, but the themes of nullification and reversal run throughout.