The movie revolves around Surjan Singh Shekhawat (played by Aamir Khan), a police officer who suffers from a rare psychological condition known as "Hyperthymesia" or highly superior autobiographical memory, which makes him remember every single detail of his life. The story takes a turn when Shekhawat's son goes missing, and what follows is a personal quest (or "talaash") for his son, intertwined with his professional duty.