There were two partners of a Hotel in Rangoon. While Jamna Dass was away, his partner Ram Lal was murdered. Jamna Dass dashed to Bombay where his daughter Nimmo has already gone. He made out a new will assigning the property to his daughter. He rang up Ashok to meet him. As he finished, he found his arrogant brother Jeevan face to face. An altercation; then a scuffle and last a gun fire sound and there lay Jamna Dass dead.
Mr. Singh, his secretary, appeared on the scene with a tape recorder in his head. A drama of black-mail starts. Both escape to Rangoon. Ashok comes over there and finds Jamna Dass dead. Frightened, he runs away. Soon, thereafter, Nimmo is kidnapped from her Hotel Room. Ashok & Murli fly to Rangoon after the culprits. A private detective, Ramesh suspects Ashok of the crime and follows him to Rangoon. There, they come across Ragini, the cousin sister of Nimmo. A romance between Ragini and Ramesh and both join hands to trace the culprit.
The news of murder of Nimmo comes and Ragini inherits the whole property. Mr Singh doubles up his black-mail of Jeevan and wants to marry Ragini. Suddenly the dead Ram Lal is found alive and a tussle starts between Ram Lal and Singh. Just at the moment, Singh & Ram Lal find Nimmo alive to tell the tale. Jeevan also comes there and Ashok and Ramesh too. Ram Lal was rounded up, but was he the killer or someone else. These are the mysteries of ‘ADHI RAAT KE BAAD’, which you will see and enjoy on the silver screen.
(From the official press booklet)