He was a soldier who fought in the Second World War. He fought in Singapore, where he first saw the Thijarians over the body of his older brother Kunal, who had died in the war, whilst his younger brother Manish was not old enough to fight.
By 17 August 1947, he had returned home and was engaged to Umbreen, his childhood sweetheart. He noticed the Thirteenth Doctor and her companions Ryan Sinclair, Graham O'Brien and Yasmin Khan, the latter of whom was his fiancée's future granddaughter, and offered them a lift to Umbreen's house on his cart.
Despite all this, Prem was never racist, instead being wise and accepting in such situations. He knew similarities between people mattered more than the differences; though he was not above making a snide remark about a country if he thought they were to blame for problems, like when he poked fun at Team TARDIS for being British.
When the Thijarians appeared again in the Punjab, he helped the Doctor and Ryan investigate their presence. Manish, Ryan, and Graham were present on the night before his wedding.
He married Umbreen on 18 August 1947 at the border of Pakistan and India in a wedding officiated by the Doctor. They performed both the Hindu ritual of having their hands tied together and the Muslim ritual of giving a treasured possession, in this case, his watch. The face shattered when he tried to give it to Umbreen but she said she would use the broken watch to remember the moment of their marriage.
When armed men encroached, Prem ordered Umbreen to flee to Lahore. Prem was killed by Manish for marrying a woman of another religion. The Thijarians watched over his death and ensured he would be remembered.
Umbreen eventually married another man, and gave her granddaughter Yaz the watch from her wedding with Prem. This sparked events that led Yaz coming to 1947 to bear witness to Prem's wedding and death. (TV: Demons of the Punjab)