Louis Mandylor was born in Melbourne, Victoria, Australia. He is the son of Greek immigrants Louise (née Mandylaris) and Yannis Theodosopoulos, a taxi driver. His older brother, Costas Mandylor, is a fellow actor. They both decided to take a shorter version of their mother's last name, claiming the original name was too long. Louis Mandylor is a film and television actor best known for his role as ‘Nick Portokalos’ in My Big Fat Greek Wedding and My Big Fat Greek Wedding 2. Before acting, he played professional soccer in Australia for four years. He played for Heidelberg United FC (Megas Alexandros) in their 1988 State League championship team. He also competed in five National League games in 1989 and scored one goal.