'Let me tell you a secret. Your Nana helped many Jewish families flee the Nazis.'

When Vinay Gupta heard of the daring exploits of his grandfather, he embarked on a journey to uncover the truth. What he found was the exceptional tale of an unassuming yet enterprising man from Punjab who chose to help complete strangers in their most dire hour of need.

The year is 1938 and Kundanlal, a machine tool manufacturer from Ludhiana, is in Vienna for a surgery. As he is recovering, he befriends Lucy and Alfred Wachsler, a young Jewish couple about to have their first child. From them Kundanlal learns of the changing political climate in Europe-the attacks against Jewish people and the Aryanisation of their businesses. As the owner of multiple factories, he finds himself in a unique position to help. Applying for visas on behalf of the Wachslers, Kundanlal sponsors them, along with four other Jewish families, providing proof of employment, financial backing and shelter. He starts new businesses to employ the men and builds homes for the families back home.

When they arrive in Punjab, the families are forced to contend with the slow pace of life in small-town India, a stark contrast to cosmopolitan Vienna. But even this interlude is fleeting as the British round up all people of German descent-Jewish and Gentile alike-and ship them to internment camps across the country, echoing in a way the events in Europe.

A Rescue in Vienna is an endearing family memoir that sheds light on a fascinating slice of history, and an unusual piece of heroism.