Dalek invasion of Earth. With Earth having been transported across space for use in the Daleks' "Reality Bomb", Luke assists the Tenth Doctor (David Tennant) and his associates, through web conferencing, in using the TARDIS in conjunction with Mr Smith and the Cardiff Rift to tow Earth back to its rightful place. Following this, Series 2 of The Sarah Jane Adventures (2008) sees Luke part ways with Maria when she moves to America in The Last Sontaran, and befriend investigative new girl Rani Chandra (Anjli Mohindra) who comes to discover the extraterrestrial activities that he, Clyde and his mother are involved with in The Day of the Clown. In the Series 2 serial, The Temptation of Sarah Jane Smith, Luke meets his grandparents in a time travel plot set up by the Trickster. In Series 3's The Mad Woman in the Attic (2009), an alien shows Luke a vision of the future in which he appears to be graduating from university at a young age. He meets the Doctor in person for the first time in The Wedding of Sarah Jane Smith and assists him in defeating the Trickster for a third time. Luke is entirely absent from the two-parter The Eternity Trap due to Tommy Knight's real-life school exams. In the series finale The Gift, Luke and Sarah's relationship becomes at times strained by the difficulties of parenting a teenager. Due to infectious alien spores, Luke becomes sick for the first time and nearly dies, spurring Sarah Jane to take up arms against their enemy. In the final part of the Doctor Who special "The End of Time" (2010), Luke is nearly hit by a car while crossing the road and talking on his mobile phone; he is saved by the Doctor prior to his pending regeneration. The Doctor then waves to Sarah Jane and Luke before stepping into his TARDIS and disappearing. At the beginning of The Sarah Jane Adventures Series 4 (2010), Luke is written out during the episode The Nightmare Man as the character departs to attend the University of Oxford after having taken his A Levels ahead of schedule, although makes regular cameo appearances episode-to-episode in communicating with his friends and mother via webcam. In the series finale, Goodbye, Sarah Jane Smith, Luke makes a full appearance in part two. He drives down from Oxford to assist Rani and Clyde against nefarious alien Ruby White