as the Tenth Doctor, without a regular companion, in several special episodes over the course of 2008 and 2009, the last of which aired on New Year's Day, 2010. In the Christmas special "The Next Doctor", The Doctor mistakenly believes he has met a later incarnation of himself in an amnesiac Londoner (David Morrissey), with whom he saves Victorian-era London. "Planet of the Dead" (Easter 2009) features jewel thief Lady Christina de Souza (Michelle Ryan) as The Doctor's one-off companion, and The Doctor is presented with a prophecy of his imminent death, with a woman telling him 'he will knock four times'. Tennant makes a crossover appearance in a The Sarah Jane Adventures two-parter, "The Wedding of Sarah Jane Smith", in which a powerful being known as The Trickster (Paul Marc Davis) also alludes to the Tenth Doctor's impending demise. In "The Waters of Mars", The Doctor tries to alter history and avert the death of one-off companion Adelaide Brooke (Lindsay Duncan); when she commits suicide, he begins to feel his mortality weigh down upon him. In the animated serial Dreamland, The Doctor is joined by two one-off companions in 1950s Roswell, New Mexico. In the two-part send-off "The End of Time", The Doctor confronts the Ood about their original prophecy and is led to contemporary Earth where, in the second part, the again-resurrected Master restores Gallifrey and the Time Lords to existence, although he redeems himself by assisting The Doctor to defeat Time Lord President Rassilon (Timothy Dalton) before disappearing alongside the other Time Lords. However, Wilfred finds himself trapped in a chamber that is about to be flooded with radiation. He knocks on the glass door four times, fulfilling the prophecy of the Doctor's death. The Doctor sacrifices his life to prevent Wilfred's death, exposing himself to 500,000 rads of deadly radiation and triggering his regeneration. He holds it back and is shown visiting several companions. He gives Donna a winning lottery ticket on her wedding day, buying it with money he borrowed from her late father in the past, saves Martha and Mickey from a Sontaran sniper, saves Sarah Jane's son Luke (Tommy Knight) from a car, introduces Jack to a romantic interest (Russell Tovey), and finally, just before regenerating into the Eleventh Doctor (Matt Smith), informs Rose in 2005 that she is about to have a "great year". As he begins regenerating once in the TARDIS,