Sita (Waheeda Rehman) and her friends go for a trip, at night Sita sleepwalks and when she is about to be killed by a train walking on the railway track, Ram (Manoj Kumar) saves her. Impressed, her father decides her marriage with him. But after her marriage with Ram, Sita discovers that her sleepwalking is not a simple sleepwalking but it takes her to the story of her past life - Chitrasen (Raaj Kumar), an artisan, is in love with the princess Sita (Neelkamal in her past life) but the king rejects him, and buries him alive. His love for Neelkamal is immortal and his soul survives for centuries to meet Neelkamal.
Sita is invited to Chitrasen's place by a song. She sleepwalks to Chitrasen's place every night. Her mother-in-law, a very cross person, believes that Sita is in love with another and gives her a tough time. One night Sita reaches Chitrasen's place and a brief conversation ends up with Chitrasen's soul becoming free and Sita falling unconscious. Ram rescues her & they lead a good life.
Waheeda Rehman won the Filmfare Best Actress Award for her role in this film.