Roots: The Somnus Foundation appears to borrow some of its screening methods and ideology from Scientology; The Doctor's explanation of "metacognitive imprinting" recalls Nigel Kneale's The Stone Tape, there is discussion of Schumann resonances. Prophecy-based doomsday cults. Neon Genesis Evangelion ("instrumentality of mankind" and "death and rebirth," as well as the goal of the Somnus Foundation)
Technobabble: A phase shift means the TARDIS has entered a zone of space-time with inherent causal discontinuities.
Psychic transubstantiation is an extremely delicate business, apparently.
Dialogue Disasters: The Doctor to Turlough: "I don't need to tell you what the implications are of a phase shift" (so he doesn't)
Dialogue Triumphs: "Where's your sense of adventure?" "In the TARDIS. In a box, marked 'Sense of Adventure'."
"Time doesn't care about us. Time doesn't care about the lives of the little people. Big events, all that huge history rolls down like an avalanche and we get crushed underneath. You push time, time pushes back. Save your mother - and someone else dies to restore the balance. That's how it works - I've seen it happen."
Continuity: The planet Ember lies beyond the edge of the Spinward Deeps, trillions of years into Earth's future. Once an observatory from which the Sleepers could watch the galaxies for signs of intelligence, it is now cold and black, warmed by the last remaining star. The Sleepers comprise the last of mankind, fleeing the Universe's collapse to entropy after they were [allegedly] betrayed and abandoned by the fleeing Time Lords. Literally held together by gruesome rusting prosthesis of metal and bone, they have developed sufficient technology to project their psyches back in time to find healthy corporeal vessels from the bodies of their ancestors (from a time immediately prior to humanity's 'big push' onto other worlds). Compatible aura types are necessary for psychic transfer.
The Somnus Foundation's glass tower is reminiscent of Rigellian design according to the Doctor (see: Future History). It has a distortion grid surrounding it which prevents the TARDIS from landing inside the building (the Doctor says this would present no difficulty for a Type 70.) The Foundation was originally a legitimate research group studying sleep disorders and neuroscience, but later developed into a cult, transforming the theories of its founder Natalya Pushkin. Conspiracy theorists believe the Foundation conducted secret research into psychic potential on behalf of the military and that the KGB experimented in mind control in the late 1920s. Eleven years ago during a huge electrical storm the Foundation's clinic burned to the ground, killing dozens of patients - the Somnus Tower presumably was built shortly afterward, acting as a base for the Sleepers and a psi-gate for their operations, dubbed 'the Migration."
Pavel's conspiracy theory research includes regular visits to secretrussia.com, 'glass curtain' and global conspiracy bulletin board. During his internet search of the Doctor he sees several different faces appear attached to the 'codename'. His reading matter includes astronaut files from project Sine, an early space catalogue, a photo of a yeti and writings by Tartokovksy (see: Links)
Years of negative emotion and mental suffering causes metacognitive imprinting ("a sort of psychic stain") on buildings such as hospitals, hence their air of unease.
In theory adjusting organic brains so that their unique electromagnetic signatures correspond can induce artificial telepathy between them. A sufficient number of so-aligned psyches in close proximity can pass the point of critical mass; transforming flesh into energy.
A materialising or dematerialising TARDIS releases chronometric particles. By sustaining a constant cycle of materialisation and dematerialisation the Sleepers trap the Ship below the Event horizon, enabling them to tap its energies as "raw flux" from the central column. The Doctor claims that at this point in Earth's history 'dozens' of time travellers and extra-terrestrials are scattered around the planet (including one out who walks past them - tall, with a blue hat.)
The Doctor and Turlough's previous exposure to the Vortex has made them both typically sensitive to a time fracture, the formation of a branch point where history is about to diverge from its natural course. Turlough's sensitivity manifests as nausea.
The Doctor's blood carries a distinctive artron energy signature and chronometric pattern that reveal him to be a Time Lord [it would also appear to be unique enough to distinguish him individually]. Among his personal possessions are a Molenski Univarius, (an all-purpose Time Lord Swiss Army knife) and a dermal regenerator to repair his injury. He feels a momentary stab of agony as the TARDIS is being tortured
Links: Resurrection of the Daleks (Turlough suspects "another" time corridor at work), The Dalek Invasion of Earth Pavel's conspiracy-theory material includes a photo of a Yeti (The Abominable Snowmen) and a copy of Tartokovsky's theory on N-Space (The Ghosts of N-Space). A cold Turlough wishes for a destination "somewhere tropical; sunny beaches and pretty girls..." (Planet of Fire). The Doctor wishes Lena "brave heart."
Untelevised Adventures: The Doctor visited Moscow previously "a hundred years ago" (presumably during the November Uprising), and though he knows the city geography well, considers himself unwelcome in the Kremlin.
Future History: There is an Earth Empire colony on Rigel VII in 2620.
World War Five takes place in the 45th century.
The Doctor claims that psychic transubstantiation will not successfully occur in the human race for "billions" of years.
'Entropy Tuesday' is the name given to the day the Universe ends; the last human descendent alive at that time is Xen.
Location: Moscow, the 21st century [circa 2017 if we take the Doctor's "a hundred years ago" comment literally]
The Bottom Line: Busy, broad, and ambitious. Singularity is a further stong outing for Turlough after Loups-Garoux, and another play which benefits from a foreign locale (Moscow could have easily been London and, consequently, business as usual.) Well cast, and though its central conceit is not entirely new, it is redeemed somewhat by the understated and downbeat epilogue.