10 MORE Great Horror Movies With Multiple Plot Twists

Sci-fi thriller The Call centres around Seo-Yeon, a young woman who keeps receiving calls from a mysterious person called Young-Sook who lives 20 years in the past.

During their chats, Seo-Yeon mentions her father died decades ago after her mother left the stove on. Young-Sook sneaks into Seo-Yeon's house and turns the stove off, so the father never died. Now that Seo-Yeon is reunited with her dead dad, she's compelled to do anything to repay her new friend.

When Seo-Yeon researches the caller's past online, she discovers Young-Sook will be murdered by her stepmother that day. After Seo-Yeon warns her, Young-Sook kills her stepmother in self-defence. But when a neighbour stumbles upon the stepmother's body, Young-Sook slaughters him to cover her tracks. And after Seo-Yeon tries to undo the caller's actions, Young-Sook starts killing anyone who stands in her way. 

Once the pair finally meet in modern time, Young-Sook makes the staggering revelation that, after saving Seo-Yeon's father, she saw Seo-Yeon turn the stove on, meaning she was responsible for her father's death all along.

After Young-Sook is pushed off a balcony, Seo-Yeon makes amends with her mother, seemingly living happily ever after... but it's not over, as a flashback reveals that Young-Sook called herself in the past, telling her to fake her own death.

Young-Sook went into hiding after seemingly dying from that fall, with the story concluding with her murdering Seo-Yeon's mother - the final shot indicating that the protagonist will be joining her very soon.