At 16, Walker graduated from Ballet Rambert School in Twickenham, began her career as a dancer, but had to abandon dancing after a leg injury at the age of 18. She then decided to become an actress. She moved from the Drama Centre in London to the Royal Shakespeare Company, where she played bit parts for six months before graduating to small roles on television.
Walker landed the title role in the television series Lorna Doone before making her feature debut in Shogun Mayeda (1991). In that same year she appeared in Les Equilibristes and in Mike Newell's Enchanted A...