The adventures of a Time Lordu2014a time-travelling humanoid alien known as the Doctoru2014who explores the universe in his TARDIS, a sentient time-travelling space ship. Its exterior appears as a blue British police box, which was a common sight in Britain in 1963 when the series first aired. Along with a succession of companions, the Doctor faces a variety of foes while working to save civilisations, help ordinary people, and right wrongs.