An unlikely group of people become trapped on a bus with Basil Joseph's character Luke PP, who is mistakenly believed to be the serial killer terrorising their community. The situation escalates as they try to figure out the true identity of the 'Banana Killer', government official SK, who has a personal vendetta against his next victim, Keshava Kuruppu. As night falls, the passengers are trapped with SK and Luke must find a way to save them from his clutches while also uncovering the truth about his own potential connection to the serial killings.