The Visitation is the fourth serial of the 19th season of the British science fiction television series Doctor Who, which was first broadcast in four twice-weekly parts on BBC1 from 15 to 23 February 1982. The serial is set in and near London in the 17th century. In the serial, a group of fugitive aliens called Terileptils plot to make the Earth their new home by spreading a deadly plague among humanity. Plot The TARDIS lands in 17th-century London. Upon stepping outside, The Doctor, Nyssa, Tegan, and Adric immediately smell sulphur and head off to find the source. Richard Mace, a highwayman and self-proclaimed thespian, encounters the group and takes them to safety inside a barn. While questioning Mace, they find out that some kind of comet recently landed nearby. The Doctor and his friends discover the "comet" was actually a spaceship inhabited by a Terileptil fugitive, who uses mind controlling bracelets to subdue the local villagers. In a nearby manor house, they find a cellar full of caged rats and a device emitting soliton gas. The Terileptil plan to use rats infected with a genetically enhanced plague to devastate the population and conquer the planet. Using the TARDIS scanner, the Doctor locates the Terileptil in London. The TARDIS rematerialises there and the five enter the building. With the Terileptil leader are two others who get the jump on the Doctor and Mace. They manage to stop them, but the Terileptil leader's weapon starts to overload and detonates. The resulting explosion destroys the building and starts a raging fire. Mace stays behind to fight the blaze as the Doctor, Tegan, Nyssa and Adric leave in the TARDIS. It is revealed that the fire is at Pudding Lane, the location where the Great Fire of London started. Broadcast and reception The story was repeated on BBC1 across four consecutive evenings from 15–18 August 1983, achieving viewing figures of 4.3, 4.6, 3.6 and 4.8 million viewers, respectively. At the time of original broadcast, the series as a whole was getting watched in 39 countries worldwide, with around 88 million viewers abroad and an average of 10 million in the domestic market. Paul Cornell, Martin Day and Keith Topping gave a favourable review of the serial in The Discontinuity Guide (1995), writing, "A good, hearty action romp, crisply written and engaging, although critics might say that it's too straight-forward. There's only one proper