Saathi (1968)

Dr. Ravi returns from abroad and takes up position as Chief Surgeon in a hospital. He then meets with Nurse Shanti, who lives an impoverished lifestyle with her ailing mother, and decides to perform surgery, but she passes away, and a guilt-ridden Ravi marries Shanti much to the chagrin of his mentor, Kaka, who had hoped that he would marry his daughter, Rajni. The couple then travel to Kashmir for their honey-moon, and then settle down to a harmonious relationship. Hoping to travel even more, their plans are interrupted by the hospital's head doctor, who wants Ravi to focus on cancer research. The couple drop all travel plans and immerse themselves in research so much so that Shanti herself becomes ill, and not wanting to become a burden, leaves. A frantic Ravi searches high and low in vain, and is subsequently devastated to learn that she has perished in a train accident. Kaka then becomes very ill and Kaki tells Ravi that the cause of his illness is Rajni's insistence that she not marry anyone except Ravi. As a result, Ravi marries her but is unable to get Shanti out of his mind. An embittered Rajni feels neglected and decides to confront him - resulting in his losing his vision - perhaps never to see again - and unable to do any further cancer research.