Harriet Jones Harriet Jones was a British politician in the early 21st century who served as Prime Minister of the United Kingdom . Biography . Early career . Harriet Jones was an unassuming career backbencher serving the constituency of Flydale North . She was at 10 Downing Street when an alien spacecraft crashed in the River Thames in 2006 . She was there to discuss plans for the Flydale Infirmary , where her mother was staying , in her " tiny little " constituency . She soon discovered that the Cabinet of the United Kingdom had been infiltrated ; the Acting Prime Minister of the United Kingdom , Joseph Green , was actually one of the Slitheen family in disguise . When the Ninth Doctor arrived at Downing Street to consult on the crash , she tried to warn his companion , Rose Tyler , of what was happening , but the two were pursued by the unmasked aliens . ( TV : " Aliens of London " ) Eventually , she was trapped together with the Doctor and Rose in the Cabinet Room and aided the Doctor in determining the Slitheen ' s weaknesses . As the only elected representative present , Jones gave the Doctor the order to launch a Harpoon missile at Downing Street , killing the Slitheen before they could trigger off a nuclear war . Jones , the Doctor and Rose survived thanks to hiding inside a sturdy cupboard within the Cabinet Room . The Doctor told Rose that Jones was destined to be a Prime Minister , elected for three successive terms , and the architect of Britain ' s Golden Age . ( TV : " World War Three " ) Prime Minister . After the incident , Harriet Jones was chosen to form a new government . ( TV : " Aliens of London " ) Her government won the election with a landslide majority . During Jones ' s tenure , she presided over the launch of the " Guinevere One " space probe . Her economic plan allowed people to be £18 a week better off , according to Jackie Tyler . It was the space programme that led to her facing an alien invasion by the Sycorax . Although the invasion was averted by the Tenth Doctor , Jones ordered the covert Torchwood Institute to shoot down the retreating Sycorax ship . Furious with Jones , the Doctor told her he could bring her down with just six words . When she stood by her actions , he whispered those six words to her aide : " Don ' t you think she looks tired ? " Soon she was fending off rumours of ill - health and facing a vote of no confidence . ( TV : " The Christmas Invasion " ) Sarah Jane Smith once asked Harriet whether the Doctor " deposed " her , to which Harriet responded , " He did . " She wondered for " a long time " if she was wrong about her actions , but years afterwards , she continued to stand by what she did . ( TV : " The Stolen Earth " ) Thanks to the Doctor deposing her , she was unable to serve the three consecutive terms that she was prophesized to do so . Later life . After leaving office Jones continued to work behind the scenes , devising ways to protect the earth from alien intrusion should the Doctor be unavailable . With the help of the Mr Copper Foundation , she developed the subwave network , an intuitive system to seek out via computer anyone who had had extensive dealings with the Doctor . Jones used the subwave network to contact Sarah Jane Smith , Martha Jones and the Torchwood Institute in an attempt to contact the Doctor . In doing so , she allowed the Dalek s to trace her signal and a squad of Daleks were dispatched to exterminate her . She remained defiant in her last moments , holding up her ID card and saying , " Harriet Jones , former Prime Minister . " The Daleks said they knew who she was , but Jones said they knew nothing of her , telling them they would face their downfall in underestimating the human race . The Daleks exterminated her . ( TV : " The Stolen Earth " ) Legacy . The Doctor later felt incredible remorse when he realised that , despite rejecting her , she gave her life to get him where he was supposed to be . ( TV : " Journey ' s End " ) The Twelfth Doctor mentions Harriet as a possible candidate when asking the Landlord who the Prime Minister was . ( TV : " Knock Knock " ) Personality . Harriet Jones was a modest and intelligent middle - aged woman who had served her community faithfully for years without any real ambition beyond that . However , she was able to adapt quickly to the reality of the Slitheen threat . She took to the role of leadership easily , proceeding to reassure the public when the crisis was over . ( TV : " World War Three " ) In a crisis , Harriet was driven and willing to take charge . She also remained cool when under pressure , even remaining calm when the Sycorax killed Daniel Llewellyn and Major Blake right in front of her for next - to - no reason . However , she didn ' t take kindly to others making jokes at inappropriate times , and was less than impressed when Captain Jack Harkness started flirting with Sarah Jane Smith over the Sub - Wave Network . ( TV : " World War Three " , " The Christmas Invasion " , " The Stolen Earth " ) After her encounter with the Slitheen , Harriet became Prime Minister and proved to be a capable leader devoted to the safety of not only her country but the entire world . However , she displayed a darker side by ordering Torchwood to destroy the Sycorax even though they were retreating from Earth . ( TV : " The Christmas Invasion " ) After that decision she wondered if she had made the right choice but eventually concluded it had been necessary to defend Earth . ( TV : " The Stolen Earth " ) Harriet was brave and selfless when she tried to convince the Slitheen to kill her , not Rose Tyler . ( TV : " World War Three " ) At the end of her life , Harriet said her life didn ' t matter if her sacrifice would save the Earth , and fearlessly faced the Daleks when they arrived to exterminate her , telling them that ultimately they will fail as they do not know what humans are truly capable of . Her sacrifice allowed the Doctor and his companions to save the whole of reality . ( TV : " The Stolen Earth " ) Jones always introduced herself by flashing her identity card and saying , " Harriet Jones , MP , Flydale North , " because her constituency was a " tiny little place " and people would not know about it . ( TV : " Aliens of London " ) Later , as Prime Minister , she continued to flash her card and say , " Harriet Jones , Prime Minister " . ( TV : " The Christmas Invasion " ) She later modified her introduction to say , " Harriet Jones , Former Prime Minister " , flashing her passport . ( TV : " The Stolen Earth " ) Harriet was very knowledgeable , though often displayed knowledge on areas she arguably shouldn ' t know about ; she knew about Torchwood despite saying herself she knew she wasn ' t supposed to , and had at least some understanding of the Osterhagen Key , a device even Jack Harkness knew nothing about , as she ordered Martha Jones not to use or talk about it the moment she mentioned it . ( TV : " The Christmas Invasion " , " The Stolen Earth " )