Doctor (Jon Pertwee and Tom Baker) and lives a dangerous life investigating alien invasions and schemes on Earth. Series Revenge of the Slitheen sets up Series 1 of The Sarah Jane Adventures (2007), depicting Luke's first day at school and his difficulties and early bonding anxieties with Sarah Jane. Luke struggles to adapt to life at school owing to his inability to lie or master humour and his apparent genius-level intellect which sets him apart from his fellow pupils. He and Maria (who is also new to the school having moved recently to the area) meet and befriend Clyde Langer (Daniel Anthony), whilst Luke makes an enemy of Carl (Anton Thompson McCormick), an intelligent boy who envies his effortless intellectual superiority. The friends discover that Carl and three members of staff at the school have been replaced by members of the alien Slitheen family from Raxacoricofallapatorius, and that Luke has assisted unknowingly their plan to switch off the Sun by providing them with the equation they needed to run the machine that will absorb its energy. Luke tricks the Slitheen into resetting their machinery and most of the Slitheen are trapped in their secret room in the school and explode. Luke, Clyde and Maria assist Sarah Jane against alien Gorgons in their second adventure, and the war-faring alien Uvodni in their third. A plot by extra-dimensional villain the Trickster erases both Luke and his mother from history in the story Whatever Happened to Sarah Jane?, although Maria successfully restores it in the second part. Sarah Jane is forced to give Luke up in series finale The Lost Boy when a couple allege that Luke is their biological son, casting doubts on his original origin. This later transpires to be a plot by the original Slitheen that Luke believed he had killed, who attempt to harness Luke's latent psychic abilities to telekinetically bring the Moon crashing into the Earth. Luke and Sarah Jane are reunited after their plot is foiled. Luke is mentioned, but does not appear, in the Doctor Who Series 4 (2008) episode "Turn Left", wherein a plot by the Trickster created an alternate reality where the Doctor is dead. Consequently, Luke, Sarah Jane, Clyde and Maria die in an alternate version of the Doctor Who episode "Smith and Jones". Subsequently, the Doctor Who Series 4 finale features Luke, Sarah Jane, Mr Smith and robot dog K9 witness a