The Doctor is an alien Time Lord who travels through time and space. The Fourth Doctor is played by English actor Tom Baker, who portrayed the character for seven seasons, the longest of any actor in the role. He is known for his iconic appearance; his mass of curly hair, imposing stature and long coat and scarf make the Fourth Doctor instantly recognisable. The Fourth Doctor’s travels alongside Sarah Jane Smith (played by Elizabeth Sladen), one of the most famous companions on Doctor Who. Tom Baker’s Doctor is one of the most famous incarnations of the Doctor of all time.