Watch Léon: The Professional (1994) HD Full Movie Free on SolarMovie. Watch Léon: The Professional (1994) online free. 12-year-old Mathilda is reluctantly taken in by Léon, a professional assassin, after her family i...12-year-old Mathilda is reluctantly taken in by Léon, a professional assassin, after her family is murdered. An unusual relationship forms as she becomes his protégée and learns the assassin's trade.