Roots: The Philadelphia Experiment, Titanic, Tenko. The Three Stooges. Charley plays 'Chopsticks' on the ship piano, while Corville plays (and the Cyberplanner later 'sings') Botany Bay. Charley calls Byron "Captain Bligh". Great Northern Railways' early 20th Century holiday posters ("Skegness - so Bracing!"), Austin Powers ("intergalactic man of mystery") The Book of Daniel ("Into the lion's den"). Charley's fate recalls Treasure Island.

Intertextuality: The Doctor's description of the TARDIS materialisation noise - a "wheezing and groaning" comes courtesy of Terrance Dicks' Target novelisations.

Goofs: Despite its use here the obsolete term 'Australasian' is no more synonymous with 'Australian' than 'European' is synonymous with 'English'.

After the events of Zagreus and The Next Life, at what point will Charley's messing up the Web of Time cease to be an issue? [Answer: never, if there's a story to be had in it!]

Why are the two Byrons so similar in motivation, voice and [it would seem] appearance? It doesn't serve the plot except make things more confusing for the listener.

Technobabble: A temporal hump is a "swelling" in space/time caused by pressure in the event ridges.

temporal corrosion is a fungal infection found in the Vortex (and a known TARDIS killer)

Double Entendres: "Byron I have no interest in booty."

"Cybermen do not discriminate according to gender."

"Soon my body will be augmented. My Cybermen are fitting conversion apparatus below deck."

Dialogue Disasters: Detective Yu's Charlie Chan patter: "So sorry".

"Make like a wallaby with its backside on fire?"

"these creatures may be iron, but they don't do irony."

"No need to get the Cyber-thumbscrews out..."

"You great Aussie drongo!"

Dialogue Triumphs: "Organ replacement time is it? Well sorry Cyberman, you're going to have twice the job with me."

"My ankles are swelling up" "Cybernetic conversion will alleviate difficulty" "And no waiting list! You can see to my hip while you're at it."

"Hope is a corruption of probable outcome. It has no value."

Continuity: Light bending technology akin to that of the Philadelphia Experiment (see: Roots and Links) is indeed similar to matter transmission technology. The equipment stored on the HMS Batavia originated from blueprints smuggled out of a similar (and potentially more successful) Japanese project. Charley deduces it works by creating a dense magnetic field which is is directed around the vessel through the ship's cabling (not bad for an Edwardian).

The Cybermen of this story are vulnerable to (and therefore wary of) gold; they measure time in spans (and 'micro-spans'). They are the remnants of a time squad sent into the future on a test flight — this was interrupted by a system failure, stranding them in the Vortex until a triangulation on the Batavia's signal allowed them to exit safely. Despite having no response to their initial distress signal to Cyber control, they later work on new directives through their Cyberplanner. The Cyberplanner can download its consciousness into another body (even an unwilling recipient.) The cyber-control signal [is] a neural worm which uses people's memories to exert its influence over their brain. Being the conduit for a cyber-control signal causes the deterioration of un-augmented brains. The cybernised Byron feels no pain when his arm is torn off.

Temporal corrosion is a fungal organism which grows in the Vortex, and is a known TARDIS killer. Under the TARDIS console there are coils of pink and blue rope.

During her childhood Charley and her family stayed at a hotel in Ostend, where she read Treasure Island. Inspired, she sent off hundreds of bottles with her name and address in them from the end of the pier to drift out to sea but none returned to her. After the Cyber ship breaks up she is stranded in the future with a crystal set she created from the debris. She has no idea what the TARDIS' HADS operation is.

The Doctor and Charley's numbered escape strategies include numbers seven (a classic move involving diversion and counter-diversion), and six. The Doctor has had a permanent suite on floor six of the Singapore Hilton since 1872 but relinquishes it in this story. In his pockets he carries a set of handcuffs and a primed mousetrap. It has been a long time since he performed a fireman's lift, He refers to his age as "nine hundred" in Earth years.

Links: This story follows directly from the end of Absolution. Storm Warning, The Chimes of Midnight (Edith) - Charley mentions "Cissy and Peg", her sisters. The Chase (Charley and the Doctor discuss Daleks boarding the Marie Celeste), The Krotons (HADS), the appearance of the Cyberplanner seems to be similar to that version in The Invasion. The Ark in Space/The Sontaran Experiment (solar flare activity forcing an evacuation of Earth), Memory Lane ("Uncle Jacques"); The Five Doctors "dialogue with organics has no validity", Revenge of the Cybermen ("resistance is futile") Charley's surprised reaction to the different Doctor paraphrases the Sixth Doctor's first words in The Caves of Androzani, Tomb of the Cybermen ("you will be made like us") The Macros (the real Philadelphia Experiment). Charley mentions the events of Invaders from Mars ("Orson Welles"), The Stones of Venice and Sword of Orion (the Garazone System). This story leads directly into the opening scenes of The Condemned. The Doctor's meeting Sigmund Freud (assuming it is the same occasion) is referenced in Doctor Who and is therefore, presumably, one which took place before his seventh regeneration (c.f. Brotherhood of the Daleks)

Qv: 'Life Inside the Vortex', 'The Doctor's Age', 'The Web of Time'

Untelevised Adventures: The Doctor taught a form of hypnotism to Sigmund Freud. The Doctor and Charley saw a form of radar-jamming device on Quaxan IV

Future History: Earth of the year 500,002 features a red sky and boiling sea with (obviously) a very warm climate. Its population has been evacuated due to solar flare activity.

Location: New Year's Eve 2007, 15 January 1942, the year 500,002

The Bottom Line: "How did you do that?" "Er... too many words, sorry"

In some ways, a deliberate rewriting and reversal of Storm Warning, where Storms' Simon Murchford, a legitimate cabin boy aboard the R-101 becomes the previously well-to-do runaway and stowaway Madeline Fairweather, passing herself off as a merchant seaman called Simons — both of course unwittingly exchanging identities with Charley on a doomed voyage. The ending when it arrives is moving enough, but the story is fussy with its timelines and tries to be too clever with multiple duplicates — some to no end (see: Goofs). Epic, possibly, but Barnes has done much better, and Charley's best send-off is still some stories away. The post-credits coda is a neat twist though.