Fourth Doctor

The Fourth Doctor is an incarnation of the Doctor, the protagonist of the British science fiction television series Doctor Who. He is portrayed by Tom Baker. Within the series' narrative, the Doctor is a centuries-old alien Time Lord from the planet Gallifrey who travels in time and space in the TARDIS, frequently with companions. At the end of life, the Doctor regenerates; as a result, the physical appearance and personality of the Doctor changes. Preceded in regeneration by the Third Doctor (Jon Pertwee), he is followed by the Fifth Doctor (Peter Davison). Baker portrays the Fourth Doctor as a whimsical and sometimes brooding individual whose enormous personal warmth is at times tempered by his capacity for righteous anger. His initial companions were the journalist Sarah Jane Smith (Elisabeth Sladen), who had travelled with his previous incarnation, and Surgeon-Lieutenant Harry Sullivan (Ian Marter) of UNIT. His later companions were the warrior Leela (Louise Jameson), robotic dog K9 (John Leeson and David Brierly), fellow Time Lady Romana (Mary Tamm and Lalla Ward), teen mathematical genius Adric (Matthew Waterhouse), teen alien aristocrat Nyssa (Sarah Sutton), and Australian flight attendant Tegan Jovanka (Janet Fielding). Baker portrayed the character for seven consecutive seasons, which remains the longest tenure of any actor to portray the lead, counting both the classic and new series. Baker's tenure as the Doctor is highly regarded among fans of the show and he is considered one of the icons of Seventies British culture.