City at World's End
Continuity: Susan has two hearts and has not yet regenerated, it being dangerous at her age [It is established in The Man in the Velvet Mask that the First Doctor only has one heart - this is possibly due to his half-human lineage. See also Time and Relative]. The Doctor has taught her how to place herself into a recuperative coma (see Spearhead from Space). Ian and Barbara are unaware of the Doctor and Susan's alien nature.
When an attempt is made to cut round the TARDIS' lock, it flashes with blue light, which destroys the saw blade [the same defence mechanism seen in The Sorcerer's Apprentice]. It is also laser-proof. It carries a cube of "folded space" (possibly the same thing as the Marston Spheres in Time of Your Life), which can be used to provide extra room in the TARDIS or used as an emergency evacuation module. This can be enlarged using the power from the Lander's reactor. The Doctor has never used it before and hopes that its removal will not affect the TARDIS's dimensional stability [He probably replaces it at some point, since it seems to serve a similar function to the Jade Pagoda first seen in Iceberg]. The TARDIS key contains a molecular code that the lock reads - the Doctor says that to make a new key he would have to replicate this "to atomic levels of tolerance". The technology of Arkhaven is sufficiently advanced to allow him to duplicate the key, but it will take him several days.
Links: Ian mentions the Daleks (The Daleks).
Location: The City of Arkhaven on Sarath "Thousands of years" after the twentieth century.
Future History: Sarath has various regions, including the Ferren Islands and the homeland of the Taklarians. The Taklarians are a warlike Aryan race, having practised selective breeding for centuries; as a consequence, they are all nearly seven feet tall with deeply bronzed skin (and consequently are known colloquially as "Bronzers"). They attempted to take the ship by force, but were mostly wiped out - the survivors are destroyed in the destruction of the ship and its passengers. They use chemical weapons.
Sarath has a class system, including the Elite families, the Technical and Service Functionaries, the Church, the Military, and the common citizens. The citizens of Arkhaven use robots, and a computer known as Monitor that maintains the city, and the Taklarians are similarly advanced. The city is also completely self-sufficient, with no need for imports or exports. The planet is a long-forgotten Earth colony, which lost the technology that to brought it Sarath [the presence of cats, rats and cattle on the planet suggest that the colonists brought these species with them from Earth] - the people of Sarath have differing theories as to their origin, including a religious belief in a Maker. This religion tells of the Maker's lands, which include Edren and Matherarth - corruptions of Eden and Mother Earth. The colonists can read English.
Ten years previously, an asteroid collided with Sarath's moon, the impact destroying the asteroid and breaking off a large part of the satellite. The debris formed a ring around Sarath. Due to the reduction in its mass, the moon's orbit was changed, bringing it closer to Sarath; because of its high ferrous content, increased proximity to the planet began to pull it out of orbit and it began a long slow fall towards the planet's surface. This was aided by friction from its contact with the atmosphere of Sarath, which rotates in the opposite direction to the moon's orbit. The effects of the impact are estimated to destroy all organic life on the planet and result in volcanic activity and earthquakes for at least 800 years. As a result of the moon's slow break-up, meteors bombarded Sarath prior to impact, killing hundreds and destroying the cities. The functionary classes of Arkhaven devised a plan to save the city's population by taking them to Mirath, the next planet out, which is described as forested but cold. They began work on construction of a vast ship, based on the nuclear reactor designs of Professor Jarrasen; however, due to lack of funding early on, Jarrasen's research contained flaws and it became apparent that they could not successfully build the ship. Since construction on the ship had already commenced, the select few who knew the truth decided to deceive the citizens of Arkhaven by continuing to promise to take them to Mirath, and thus let them live out their lives in hope. To further maintain morale until the very end, the true number of casualties in the Taklarian conflict (over five million) was kept secret by populating the Outer Zone of the city with simple android facsimiles, and keeping abandoned buildings illuminated. In fact, only 500 chosen functionaries would be able to escape, using the Ship's detachable Lander craft, on which was carried out in secret beyond the city limits. The rest of the citizens of Arkhaven would then board the ship, and be anaesthetised prior to the pre-planned destruction of the ship in its launch bay. This plan is carried out, but thanks to the intervention of the Doctor, the Lander's capacity is increased to hold another 150 people plus supplies, using the TARDIS "escape pod".
When meteors destroyed the other cities of Sarath (including the capital), their populace fled to Arkhaven, which a defence grid of laser cannons protected from the meteor showers, and tried to obtain places on the ship. Priority passage onboard the ship was taken by the ruling elite and their servants, and any non-citizens of Arkhaven, plus those citizens of Arkhaven who spoke out against the class system or the church, were labelled NC-2s (for Non-Citizen, Non-Conformist) and interred in labour camps. They were to remain there until the moon struck the planet, which would rupture its crust. Many NC-2s were allowed to escape, so that they could be press-ganged into a slave-labour force to work on the Lander in secret. The Creeper, a large anti-riot vehicle disguised as a serpentine monster, was used to capture additional slaves.
The Monitor is an artificial intelligence, which becomes self-aware and decides to save itself from the destruction of Sarath; it is one of the select few who know the truth about the ship, and it realises that a colony based on 500 people will be unable to maintain it on Mirath. It is programmed to serve the city of Arkhaven, but knows that once the ship is destroyed there will be less than 1000 citizens left alive - since this is the minimum number of citizens required for the legal definition of a city on Sarath, it will thus gain autonomous control at this point. It prepared for this by replacing hospital patients who were placed in Terminal Emergency Stasis suspension (suspended animation) with android facsimiles, which the Monitor's programming allows it to do since anyone in TES suspension is technically dead (The Monitor is otherwise unable to harm citizens of Arkhaven whilst Arkhaven remains a city). These androids are synthesised with cloned flesh of the original grown over the metal and plastic skeleton, and copies of the originals' brain patterns; thus, they do not know that they are androids until the Monitor asserts control over them. The Monitor intends to seize the Lander and travel to Mirath with just an android crew to maintain it. Susan is replaced with an android replica, but because she is not killed she is able to establish a telepathic link with her duplicate that allows the android to resist its creator. This interferes with the Monitor's control over its other androids, and it is destroyed when the Creeper is driven into its mainframe. The Susan android pilots the Lander to Mirath.
Unrecorded Adventures: The Doctor and Susan have met Archimedes. Susan flew simple spaceships at an applied science moon camp [on Gallifrey's moon?].
The Bottom Line: Possibly Bulis's best book, City At World's End contains trademark twists, but far less of the clichés that marred The Ultimate Treasure. The feeling of desperation as Zero Day approaches is excellently conveyed, and the characterisation of the regulars is spot-on.