Due to the anthology having its release date pushed forward, it was the first audio released to feature the Doctor's companion Constance Clarke, before her actual debut story was released.
The Doctor and Constance Clarke find themselves lost in the fog. Luckily, they’re not too far from Kettering Junction, a Midlands railways station that service a large among of daily commuters heading to London. They’re not alone – passengers and staff from a nearby commuter train have made their way to the station after their train stopped. Meeting a local trainspotter, the Doctor and his fellow travelers soon make several discoveries. One, Kettering Junction should have twelve platforms, not seventeen. Two, each platform holds an identical commuter train, some in pristine condition and other caked with blood. And three, there are distant and bloodcurdling screams coming from the fog – screams that exactly like those of the passengers and staff…
Parallel universes aren't supposed to meet, hence the word 'parallel,' but there are various points in the universe where the parallels collide.
There are other dimensions that, while they can't be called "evil" since that's too subjective, are nonetheless darker, but these darker dimensions are usually "safely" away from the nice ones.
The Normans are "Normal Animates," since "normality" can have various meaning in different realities. They were grown by the Parallel Sect.
The longer the dimensional barriers are broken, the more dimensions collapse into infinity with accelerated "normative entropy".
The Master's TARDIS is disguised as a ticket machine. The Doctor notes to Constance that the Master's TARDIS, much like the Master, is a "master of disguise".
Keith Potter is an avatar, operated by the Master from the safety of his TARDIS.
The Valeyard claims the dimensional nexus point as his domain, where he's been re-invigorating.
Notes
This story contains the first released appearance of companion Constance Clarke, portraying her as already travelling with the Sixth Doctor. Due to the release date of The Sixth Doctor: The Last Adventure being pushed forward from September 2015 to August 2015, this story was released before the story which officially introduced Constance and portrayed her joining the Doctor on his travels.[1] Her first chronological appearance is in AUDIO: Criss-Cross.
The idea of darker dimensions originates from The Dark Dimension, a cancelled anniversary special where the Fourth Doctor's death was prevented, creating a "dark dimension."
The Doctor refers to his darker self who he knows is still out there, despite trying to rectify the matter. (AUDIO: Trial of the Valeyard)
According to Norman, the Master has been referring to himself as the "definite article". The Fourth Doctor once referred to himself in the same way. (TV: Robot)
After his true identity is revealed, the Master says, "Oh, my dear Doctor, you have been naive." He previously said this after revealing himself to the Fifth Doctor on 3 March1215. (TV: The King's Demons)
According to one account, the Master had the appearance of Roger Delgado while on Gallifrey. According to another, he had Anthony Ainley's likeness. According to another one, the one with James Dreyfus's appearance was the incarnation who ran away from Gallifrey.
While fighting to extend his life at the end of his regeneration cycle, many bodies were possessed by the Beevers incarnation, but all kept somehow reverting to his real being until he finally regenerated into the MacQueen one. Hence, these sections cannot be strictly chronological
