Behind You ( short story ) Behind You was a December 2014 online novella published on the " Doctor Who " website as part of the 2014 Adventure Calendar . It was released in three parts . Summary . The Doctor loathes panto but when the TARDIS brings him to the Palace Theatre at Christmas , 2014 , he has more than bad puns and pantomime dames to worry about . Like the monstrous figures that stalk the backstage corridors , a mystery stretching back over a century and the possible destruction of the entire human race . The stage is set . Can the Doctor prevent tragedy on a terrifying scale or is it curtains for mankind ? Plot . Part one . Ceri is an understudy backstage at the Palace Theatre ' s Christmas pantomime . She see the shadow of a figure with a stag head , and assume its her friend Tom playing a trick on her . She follows it , and it turns around to reveal it has an actual stag head , but on Tom ' s body . It says , " The revel begins . " Ceri , terrified , runs into the props room , where she finds the Twelfth Doctor . He asks her why , if the show is going on , they haven ' t heard any noise . They go to the auditorium to investigate . The audience is frozen in time . On stage , the lead actress Jade ' s head turns into a fox , and she says " The revel begins ! " Part two . The Doctor scans Jade with his sonic , and says the spotlight has changed her DNA and made her a hybrid . A spotlight comes down on George Hollis , turning his head into a badger ' s . George grabs the Doctor , but before he forces him into the spotlight , Ceri shoves the pumpkin prop onto the hybrid ' s head . The pair escape the auditorium . The Doctor brings Ceri to his TARDIS , and tells her he had been tracking a Light Ship to Bishop ' s Palace , 1902 , but had been thrown off course to the same theatre in 2014 . They arrive in the earlier time period in the theatre ' s pantry . Outside , there is the man with a horse head , but he is actually a pantomime horse . He says , " The revel begins – so won ' t you join in ? " They follow him to the ballroom where the audience and mummers are gathered . Ceri compares the repetition of the phrase by the hybrids to actors learning lines . The Doctor tells her he knows where the Light Ship is from , and it could mean the end of humanity . Part three . Back in the TARDIS , the Doctor tells Ceri about the planet Proscenia . It is inhabited by the energy beings Addos and humanoid Logos . The Addos create works of light for the appreciation of the Logos . When the Addos ' s Light Ship crashed in 1902 , they went into hibernation . When the appreciation of the crowds in 2014 woke it up , it tried to recreate what it had last seen to repair its ship . It will keep going until the whole planet is transformed . Ceri says she has a plan . Audience members are starting to be transformed as Ceri and the Doctor enter the stage . They ask for the audience to participate , and the hybrid cast is closing in . One boy starts it , and the whole crowd begins to laugh . Jade turns back into a human , but the Doctor says the laughter isn ' t enough to repair the ship . Ceri begins to tell the audience the story of the Doctor , and he soon joins in . The audience ' s psychic energy repairs the Light Ship and the Addos departs in a burst of red , green , and gold . Ceri and the Doctor say their goodbyes , but she notices the sadness in his eyes . Notes . " to be added "