Black Orchid is the fifth serial of the 19th season of the British science fiction television series Doctor Who, which was first broadcast on BBC1 on 1 and 2 March 1982. The serial is set in an English estate in 1925. In the serial, the alien time traveller the Fifth Doctor (Peter Davison) investigates the murder of two servants during a fancy dress party. This story was the first purely historical adventure for the Doctor—featuring no science fiction elements save for the TARDIS and the regular cast—since The Highlanders (1966). Sarah Sutton plays two characters in this story. Plot 11 June 1925: the TARDIS crew encounters Lord Cranleigh's chauffeur, who has been expecting "the Doctor". Lord Cranleigh asks them to stay until the annual ball and offers them costumes. They are introduced to Ann Talbot, Lord Cranleigh's fiancée, who looks identical to Nyssa. When Tegan admires a black flower, Lady Cranleigh explains it is a black orchid and was found on the Orinoco by her son, the famed botanist George Cranleigh. The Doctor picks a Harlequin outfit to wear to the ball. Ann comes to their room, presenting Nyssa with a dress identical to her own. As the Doctor prepares for the ball, a figure enters his room from a secret passage. The Doctor enters the secret passage, where he finds the dead body of one of the servants. The figure steals the Harlequin costume, joins the party, and attacks Ann Talbot. When a butler rushes to her assistance, the Harlequin strangles him to death before returning the costume to The Doctor's room. Lord Cranleigh finds the dead butler. The Doctor arrives wearing the Harlequin costume and Ann identifies him as her attacker. The Doctor is arrested for murder, his companions accused of being accessories, and all are taken to the police station. The Doctor clears his name and uses the TARDIS to return to Cranleigh Hall, where the figure has lit the place on fire and taken Nyssa hostage. The murderer is revealed as George Cranleigh, who disappeared during an expedition into the Brazilian forests. The local natives removed his tongue because they held the Black Orchid sacred. Losing his mind, he was rescued by another tribe. The Doctor convinces George to release Nyssa. Charles approaches his brother to thank him, but George recoils and falls off the roof to his death. Before the Doctor departs, Ann gives Tegan