The Call

In 2019, 28-year-old Kim Seo-yeon travels to her childhood home to visit her estranged mother in the hospital. During her trip, she loses her cellphone, setting off a chain of events that leads her to unexpected revelations.

While searching for her phone, Seo-yeon discovers an old cordless phone in her home. When she uses it, she receives a disturbing call from a woman claiming to be tortured by her own mother, igniting Seo-yeon's curiosity and concern.

Seo-yeon learns that the voice on the line belongs to Oh Young-sook, a girl from 1999. The two discover their ability to communicate through time, highlighting the grim circumstances of Young-sook's life as an orphan mistreated by her adoptive mother.

During their exchanges, Seo-yeon opens up about her traumatic past, which includes the tragic loss of her father in a fire. This event has left a scar on her relationship with her mother, and her blame for the incident intensifies the emotional connection with Young-sook.

Young-sook learns about Seo-yeon's father and the fire that took his life. Determined to help, she sneaks out to prevent this tragedy, altering the outcome of Seo-yeon's present and creating a new reality where her parents are alive and well.

With the fire averted, Seo-yeon experiences a joyful life with her parents in a luxurious home. However, this happiness comes with unexpected consequences for Young-sook, who faces severe punishment from her adoptive mother for her defiance.

Seo-yeon starts investigating the fate of Young-sook online, discovering that she was ultimately killed during an exorcism. This revelation intensifies Seo-yeon's desire to protect Young-sook from a grim future.

In a fight for survival, Young-sook takes drastic measures and commits murder as a means to escape her dire situation. This desperate act leads to her being labeled a serial killer, raising the stakes in her and Seo-yeon's conversations.

In the present, Seo-yeon enjoys a family dinner with her parents, although her thoughts are disturbed by the dark turn Young-sook's life has taken. Tension rises as Seo-yeon reflects on the interconnectedness of their fates.

As Seo-yeon attempts to understand the unfolding situation, 8-year-old Seo-yeon and her father inadvertently enter Young-sook's dangerous life while finalizing their house purchase. The situation escalates when Young-sook captures Seo-yeon's father, intensifying Seo-yeon's turmoil.

As the chaos unfolds, Seo-yeon finds a chilling message, 'pick up the phone!' scrawled on the floor. This message serves as a desperate reminder that time is of the essence for both her and Young-sook.

Seo-yeon discovers vital information about a gas explosion linked to Young-sook's past. Motivated by this revelation, she devises a plan to lure Young-sook into a trap, desperate to save her father and control her own fate.

Tension escalates as Seo-yeon confronts Young-sook in a battle for survival. This climactic showdown leads to violent confrontations that test their resolve and unravel the intertwined fates of both characters.

In a gripping flashback during the mid-credits, Young-sook revisits her earlier intervention that foiled her own demise. This act alters the timeline irrevocably, leaving Seo-yeon's fate hanging in the balance as haunting screams echo.