Prabhavati's (Kamlesh Kumari) parents died when she was very young and the onus of looking after the Prabhavati Cotton Mills Ltd. has come to her. Her entire focus is on the factory and she is a strict and hardworking proprietor. Her only close companion is Dr. Sethi but even here there is a reserve. Prakash (K. L. Saigal) works at one of the machines in the mill. He finds that the machines they are working on are old and dangerous. He designs a safer and more efficient one and takes the design to the President of the company. She gets angry at his suggestion that the machines in her factory are dangerous and fires him. Prakash is out of a job and looking desperately for any form of income. He meets a young girl Sheela (Leela Desai) outside a girl's hostel with whom he gets friendly. The girl unknown to him is Prabhavati's younger sister. The day Prakash is sacked from his work, the man who took his place at the machine has an accident. This gets Prabhavati thinking and she goes to Prakash's home to accept his design and re-instate him as head of the design unit. Over a period of time Prabhavati finds herself getting attracted to Prakash, without realising he's in love with her sister Sheela. During a conversation Sheela comes to know that Prabha loves Prakash. Sheela is devoted to her sister and feels deeply indebted to her for single-mindedly taking care of her and the factory. She leaves home and her attitude towards Prakash changes. Prakash unable to understand her behaviour takes out his frustration at work becoming despotic with the workers. The workers revolt and there is a showdown at the factory. Pratibha rushes to the factory; she manages to find what is troubling Prakash. Appalled at the situation she locks herself in her office and works herself into a state where she collapses.