Luke Smith is a fictional regular character played by Tommy Knight in the British children's science fiction television series The Sarah Jane Adventures, a spin-off of the long-running series Doctor Who. Luke is a regular character in The Sarah Jane Adventures both in television and audio adventures. He has also appeared in three episodes of Doctor Who: the two-parter "The Stolen Earth"/"Journey's End" (2008), and the Tenth Doctor's finale episode "The End of Time, Part Two" (2010). Within the narrative of the series, Luke is a human archetype, created by alien species the Bane from thousands of DNA samples, who comes to be adopted by the series' heroine, Sarah Jane Smith (Elisabeth Sladen). Luke is something of a child prodigy, showcasing a remarkable degree of genius but also a level of social ineptitude owing to being born in adolescence. Character history Introduction Luke Smith is introduced as "the Archetype" in the first episode of The Sarah Jane Adventures, the New Year's Day special "Invasion of the Bane" (2007). The Bane known as Mrs Wormwood (Samantha Bond) creates the Archetype from thousands of samples of DNA taken from visitors touring their Bubble Shock! drink factory. This enables the Bane to run tests on an archetypal human. Luke appears to be an ordinary adolescent boy, except for his lack of a navel having been grown rather than gestated and born naturally. He possesses a superhuman intelligence and an exceptional eidetic memory. During one tour of the factory, an alarm is set off when visitor Kelsey Hooper's (Porsha Lawrence Mavour) mobile phone disturbs the Bane Mother. The Archetype awakes and proceeds to escape with visitor Maria Jackson (Yasmin Paige) and her investigative journalist neighbour, Sarah Jane Smith (Elisabeth Sladen). After the Bane Mother sends assassins to kill the group, they return to confront the Bane. The Archetype saves the day by recalling an exceptionally long sequence of numbers necessary to trigger an explosion in the Bubble Shock! factory. In the episode's dénouement, Sarah Jane adopts the boy, naming him "Luke Smith", having also considered the names "Harry" and "Alistair" after her friends Harry Sullivan (Ian Marter) and Brigadier Sir Alistair Lethbridge-Stewart (Nicholas Courtney). Her sentient supercomputer Mr Smith (voiced by Alexander Armstrong) forges and distributes all the necessary paperwork to formalise the adoption. Sarah Jane reveals to Luke and Maria that she is a former time traveller, having been a companion of the