The first doctor in colour from 1970 to 1974 when tom baker took the fort of the tardis.pertwee was a menacing middleaged child like doctor and with his venitian combat he was grounded on earth and never travelled in anything else than the yellow car with faithful companions jo and sarah.he was the second doctor to work with u.n.i.t (united nations intelligence taskforce now known as the unified intelligence taskfore)