Lonsdale was born in Paris and raised by a French mother and an English father, initially on the island of Guernsey, then in London in 1935, and later, during the Second World War, in Casablanca, Morocco. He moved to Paris to study painting in 1947 but was drawn into the world of acting instead, first appearing on stage at the age of 24. He also plays the voice of Hugo Drax in the 007 Legends.