KEDARNATH is a love story that takes place right before a natural catastrophe. Mansoor (Sushant Singh Rajput) is a 'pitthoo' aka porter who carries pilgrims to the holy Hindu town of Kedarnath from the base. His Muslim identity doesn't come in the way of fulfilling his duty and believing in the faith in Kedarnath.
Another resident of Kedarnath is Mandakini aka Mukku (Sara Ali Khan). Her father Briraaj (Nitish Bharadwaj) is a priest and he owns a lodge and a shop on the way to the temple. He has fixed her marriage with Kullu (Nishant Dahiya), a big name in the temple town. Mukku is against this marriage as she doesn't love Kullu.
Also, Kullu initially was to marry her sister Brinda (Pooja Gor) but then he decided to opt for Mukku instead. Mukku meanwhile bumps into Mansoor and love happens. Kullu anyways hates Mansoor due to his Muslim identity. When he finds out that both Mukku and Mansoor are having an affair, it leads to madness. What happens next forms the rest of the film.