Time Wake ( short story ) Time Wake was a Sixth Doctor / Peri short story in the 1986 " Doctor Who Annual " . It was notable for being the only known " Doctor Who " story to feature " every " British Prime Minister to date of its publication . Summary . The Sixth Doctor is chasing a time anomaly in the London of 1986 . Locating it in a sewer , he is able to better define it . It ' s a Time Wake — a literal wake in the time vortex that connects 1986 to 1720 . It ' s caused by the use of primitive time travel technology . To close it , the Doctor has to stop whoever is using that technology . He decides the best way to do that is to follow the Time Wakes back to their source . He and Peri step through the wake — manifest as a circle of shimmering blue - white light — and end up in 1720 . Specifically , they ' ve arrived in the cellar of an inn . As they adjust to their surroundings , they see dozens of people around them . The Doctor recognises them as every British Prime Minister from Robert Walpole to Margaret Thatcher . He also comes to understand that they aren ' t the " actual " PMs , but android copies . As he and Peri puzzle out why anyone would bother making these copies , a shadowy figure locks them in the cellar from the outside and the androids spring to life . They threaten Peri and the Doctor , but the Doctor isn ' t overly concerned . He makes a few adjustments to the device he was using to track the time anomaly . Soon he ' s broadcasting a radio frequency that controls the androids . Easily escaping the locked door , he leads the androids out of the cellar — and directly to the Thames . They " die " a watery death . Peri and he return to the inn , where they find the primitive time machine at the heart of this mystery . The Doctor removes its Primary Polarity Enhancer , a silvery cube without which it cannot function . They intend to return to 1986 through the Time Wake , thereby leaving whoever is doing all this dangerous time travel stranded . Peri notes that the Time Wake is shrinking . They " must " get through it " now " or they ' ll be stranded in 1720 . As they near their goal , a blue - skinned figure blocks their progress . He reveals himself as Tasq , a Time Engineer from the planet Bestonas . He says that his vessel crashed in 1986 , and explains that he needed to create the prime ministerial replicas to get off Earth . By controlling the prime ministers , he would divert more money into scientific research throughout history , hugely advancing the technology of human ity . This would alter history in such a way that humans would have developed intergalactic vessels by 1986 , allowing him to escape . Clearly , the Doctor is not pleased at this revelation . He pulls the Primary Polarity Enhancer from his pocket and calmly begins to strike a deal with Tasq . While he ' s doing so , he orders Peri to go through the ever - shrinking Time Wake . He offers Tasq the opportunity to be taken back home in the TARDIS . Unfortunately , Tasq doesn ' t believe the Doctor has such a vessel . The Doctor doesn ' t like being called a liar . So , he jumps through the Time Wake , still in possession of the silver cube Tasq needs so desperately . Tasq tries to follow , but the Time Wake can no longer accommodate him . In 1986 , the Doctor and Peri watch as Tasq ' s hand comes through , then fades away . The Doctor tells Peri that Tasq died as the time vortex healed itself . The duo surface from the sewer and head towards the TARDIS . Realising he ' s been in the sewer a bit too long , the Doctor claims to need a bath .