Whatever Happened to Sarah Jane?

Sarah Jane receives a puzzle box from a Veron Soothsayer, with the instruction to give it to the person she most trusts. Sarah Jane gives Maria the puzzle box. A meteor is on collision course with Earth, and Sarah Jane has set up, but not yet activated via Mr Smith, a force field to deflect the meteor. The next morning, Maria wakes to find that Sarah Jane and Luke have gone missing, but no one besides Maria knows who Sarah Jane or Luke are. A woman called Andrea Yates has apparently taken Sarah Jane's place.[1]

Investigating, Maria finds a 1964 newspaper report, stating that a thirteen-year-old Sarah Jane Smith died after falling off a pier, where she was playing with her friend, Andrea Yates. As Maria watches, the names of the deceased and the survivor on the report switch before her eyes and, at one point, hears Sarah Jane's disembodied voice calling out to her. When Maria goes to Andrea to talk to her about the report, Andrea suddenly panics and unceremoniously shows Maria out before she rushes to her attic, where she takes out a second puzzle box. She now remembers a mysterious hooded figure, who appears and offers to make Maria disappear. After Andrea accepts, he dispatches a small alien, a Graske, who captures Maria just after her father, Alan, picks up the first puzzle box, which Maria dropped during her escape from the Graske. When Alan's ex-wife Chrissie comes round, he discovers she cannot remember their daughter. Meanwhile, Maria escapes from the Graske and finds herself on a beach promenade near two girls. They introduce themselves as Andrea Yates and Sarah Jane Smith.

After failing to dissuade Andrea and Sarah Jane from going to the pier, Maria is recaptured by the Graske and taken to join the adult Sarah Jane on a white misty plain, limbo. The mysterious figure explains he has removed Sarah Jane from Earth's timeline so the meteor will destroy it and create the chaos on which he feeds; The Doctor will be his next target.

Alan accompanies Chrissie to Andrea's birthday party. Remembering Maria's suspicions, he questions Andrea, who takes him to the attic and sorrowfully reveals the truth. When Andrea fell off the pier and Sarah Jane was unable to save her, a voice offered to switch the girls' places and Andrea, terrified, accepted. The figure appeared and gave Andrea the puzzle box, then removed himself from her memory; Maria's questions made Andrea remember the deal she made with the figure. Alan is now chased into the street by the Graske but he knocks it down, then uses its device to bring back Maria.

They return to the attic, where Sarah Jane appears in the mirror and explains to Andrea that witnessing her death gave her the resolve to fight pointless deaths herself. When the figure reappears (called The Trickster by Alan), Andrea explains she has changed her mind about the deal and throws her puzzle box at the mirror, smashing both. Back in 1964, Andrea falls to her death. Sarah Jane and Luke reappear in the attic and activate Mr Smith. The party guests, including Chrissie and Clyde, have learned from television news about the incoming meteor, and are relieved to see it suddenly diverted from its fall. The episode ends with Alan demanding an explanation of Maria's involvement with aliens and supercomputers.

• The Graske also featured in the interactive episode of Doctor Who, "Attack of the Graske". Sarah Jane states that there was Graske activity on Earth a couple of years ago, possibly referring to that episode.
• Sarah mentions previous times she saved the Earth and thwarted alien invasions, including the Bane ("Invasion of the Bane"), the Slitheen (Revenge of the Slitheen) and the Gorgons (Eye of the Gorgon). She also mentions that she helped defeat the Patriarchs of the Tin Vagabond. The Church of the Tin Vagabond was previously mentioned in the 2006 Doctor Who episode, "The Satan Pit".
• The Trickster threatens the Doctor when in limbo. This is the second time that the Doctor has been explicitly named in the series, the first being in Revenge of the Slitheen. The Trickster makes good on this threat in the Doctor Who episode "Turn Left", when a creature from "[his] brigade" assaults Donna Noble.
• Sarah Jane's address is identified as 13 Bannerman Road, as it is throughout the later series; it had been 21 Bannerman Road in the preceding two serials,[2] yet the sign on the brick wall next to the Smiths' driveway still says 21.

• Whatever Happened to Sarah Jane? title listing at the Internet Speculative Fiction Database