The Ripple Effect ( short story ) Publisher ' s summary . When the TARDIS lands on Skaro , the Seventh Doctor and Ace are shocked to discover the planet has become the universal centre of learning , populated by a race of peace - loving Dalek s . Ever suspicious of his arch - enemies ' motives , the Doctor learns of a threat that could literally tear the universe apart . . . Plot . Ace is helping the Doctor work on the console . They are stuck , with many other ships , in the Temporal Plexus . The Doctor devises a plan to escape , but the idea doesn ' t sit well with Ace . Ace sees a Police Box , and assuming it ' s a different TARDIS , asks the Doctor if all Time Lord s have TARDISes . He says yes , and asks Ace why she asks . She says she saw a police box , but the Doctor dismisses the idea , blaming it on a temporal echo . The Doctor and Ace escape the Plexus by causing a nearby star to Nova . In the process , he causes the Cloister Bell to ring . The Doctor explains they are being flung across space and time . Ace is relieved when she hears the sound of the TARDIS landing , but the Doctor says it is just an auto - land . They land on a planet , and when the Doctor opens the doors , they hear children playing . While the Doctor is tinkering with the console , Ace sees a Dalek glide through the open doors . The Doctor uses the quantum stabiliser to stun the Dalek . He notices that the Dalek doesn ' t have a ray gun , instead it just has two manipulator arms . Just then , a small crowd of children from assorted planets rush in . One girl , Tulana , confronts the Doctor . She takes the quantum stabiliser , and then three more Daleks come in . One blocks the door , while the other two approached their fallen comrade . One of the Daleks , Pytha , apoligises for his colleague , Sokar . He invites the Doctor for a tour of the academy after lunch . The group leaves , and Ace and the Doctor try to piece together what just happened . The Doctor concludes that they are on Skaro , however he knows that is not possible because Skaro doesn ' t exist anymore . He goes off to the bowels of the TARDIS to check the computer systems . An hour later the Doctor finishes his research , and concludes that these nice Daleks are " instead " of the evil ones , instead of an earlier hunch that they were a renegade faction . Skaro has become the universal centre of civilisation , philosophy , democracy and art , similar to ancient Greece . They are then escorted to lunch by Tulana . Ace notices that the food they serve on Skaro is very different to the food on Earth , so she eats whatever Tulana does . When lunch has finished , Tulana takes them on the promised tour of the Academy . During this , the Doctor is scolded by a Dalek for his comment on ancient Greece . The Doctor tells Tulana about the Daleks he knows , but she explains that the accidental Neutron War caused them to mutate . She claimed that the Daleks the Doctor had met could be criminal Daleks , or even impersonators . Tulana takes them back to the main building , and rambles about the majestics of Skaro . The Doctor offers to take her on a tour of the jungle of Skaro , and Tulana agrees . They spend an hour zipping around Skaro . On their way back , the Doctor discovers a fleet of Dalek spacecraft , the surround Daleks fully armed . When the Doctor confronts Tulana , she simply says that the Daleks need some way to protect themselves from attacks . The Doctor returns Tulana to the Academy . The Doctor spends the next few hours grumbling around the TARDIS , checking TARDIS archives and re - calibrating instruments . The Doctor eventually gives up , and is convinced by Ace to go to Gallifrey to talk to the Time Lords . Tulana is noticed on the monitor , and is let in by Ace . She hurriedly asks if the Doctor is going to see the Time Lords . The Doctor is amazed at how she knows he is going to Gallifrey . The Doctor doesn ' t want to take Tulana with them , but Tulana says she ' ll walk instead . The Doctor asks where she thinks she ' s going , and she replies that the High Council are at the hall to congratulate a Dalek medical team for operating on their Lord President . Tulana walks off , and the Doctor calls off his visit to Gallifrey , declaring that there is no point . Any change on the universe that big that happens without the Time Lords realising would be extremely dangerous indeed , he tells Ace . The Doctor starts treating the Daleks like friends . Tulana is surprised , and asks why the Doctor has changed . He simply explains it on some sort of alternate timeline . He then explains to Ace that he has to fix it , or else the entire Universe could collapse from Space - Time decay . He converts the TARDIS into a vortiscope , and discovers the terrible truth that he caused the alternate timeline in their escape from the Plexus . He explains to Ace that the ' echo ' she saw was actually their future , looping themselves back into the Plexus . The TARDISes were twisted together , and the energy caused when they were released was enough to cause the alternate timeline . He tells Ace they have to go back to the Plexus to fix it , but Ace doesn ' t want to say goodbye to Tulana and her new friends . Suddenly , a massive wave of decay ripples underneath them . Pytha requests for the Doctor ' s help , as the Universe begins to crumble . Ace asks the Doctor what would happen to Tulana if they fixed things . He explains that Tulana was a Markhan , and their race was wiped out by the Daleks , two hundred years ago . The Doctor restores the chrono - dynamic parity , and him and Ace merge with the other TARDIS . His plan works , and after a quick back - track to Skaro , he discovers that the universe has been restored . References . " to be added "