A maths nerd, a weird webzine publisher and the Brigadier find themselves helping the Seventh Doctor and Ace to solve the puzzle of a crop circle in the Kentish countryside. Only itŐs not a circle but a series of square-sided shapes, and itŐs filled with ice. And it seems to be causing time anomalies..
Ace and the Brigadier.
Pg 6 The junkyard, 1963 (slightly before the events of Remembrance of the Daleks).
Pg 8 Baltimore, 3 October, 1849.
Pg 12 Antarctica, 17 March 1912.
Pg 146 We don't see it happen, but the TARDIS has materialised in the back garden of the house on Allen Road, present day.
Pg 167 Switzerland, present day.
Pg 220 The TARDIS has returned to the house on Allen Road.
Nothing particular, but this emulates the style of the NAs in general, so a passing familiarity with them is nice, but not essential.
Pg 6 "She and the Doctor were in an alley ending at a pair of sagging, chained-together junkyard gates bearing the weathered letters "I M Forman"." This is the junkyard, slightly before Remembrance of the Daleks is due to start. It also appears in An Unearthly Child and Attack of the Cybermen.
Pg 7 "Not "Foreman" with an "e"." The two spellings refer to the continuity error in Remembrance, whereby the junkyard sign was misspelled from its version in An Unearthly Child.
Pg 26 "Like that time he'd pretended to Fenric he thought she was stupid and useless..." The Curse of Fenric.
Pg 32 "Oh, Yetis in the Underground. That sort of rubbish." The Web of Fear.
Pg 48 "Long ago, in his fourth body, he had been given the chance to destroy the Daleks and hadn't." Genesis of the Daleks.
Pg 49 "Never again, please never again, in all his future lives, let him exterminate an entire race." Sadly, the Doctor will go on to do this several times: with the Time Lords in The Ancestor Cell and both the Time Lords and the Daleks in the Time War.
Pg 67 "You won't like what you find at the centre of the Earth" Inferno.
Pg 88 "'You're not green.' 'The Edrecki are.'" Uncertain reference.
Pg 154 Reference to the fifth Doctor.
Pg 156 "I think his lot reproduce by being woven from DNA or something naff like that." The Looms, first mentioned in Time's Crucible and seen in detail in Lungbarrow.
Pg 157 "She opened the wardrobe and pulled out a harlequin-patched coat." The sixth Doctor's jacket.
"She sighed and pulled out a brown velvet frock coat that was much too large for him." The fourth Doctor's jacket.
"You should have seen him when I first met him. Something out of an old clothes bin he was." Seasons 24 and 25 in general and Dragonfire in particular.
Pg 168 "She went into the little kitchen annex off the food-machine room." The food machine was first seen in The Daleks.
"In bathing costume and terry-cloth robe she started down the corridor that led from her bedroom to the pool. It was about a five-minute walk with, it had always seemed to her, a needless number of turns." The pool was first seen in The Invasion of Time, complete with a needless number of turns. The Doctor had deleted it by Paradise Towers, but it was back again in the NAs, so we can presume he reinstalled it not long after deleting it.
"Something else always took his attention. Giant metal insects or something." Ace will eventually encounter giant metal insects, in Set Piece.
Pg 177 "Ethan was also provided with a soft, wide-brimmed hat that looked to have gone a few rounds in its day." The fourth Doctor's hat.
Pg 179 "Then I got caught up in this time storm and carried away to this ice planet and then what happens? I'm a waitress! And I get involved with a prat anyway, only he's about forty years older than I am." Dragonfire and her affair with Glitz (hinted at in the Dragonfire novelisation and confirmed in Happy Endings).
Pg 184 "WHAT IS SKARO? HE DESTROYED IT" Remembrance of the Daleks.
Pg 186 "I blew up a planet." Remembrance of the Daleks.
Pg 187 "'It wasn't my home planet I was destroying.' Brett smiled again. 'Well, it's early days yet. They say the second crime is always easier.'" The Ancestor Cell.
Pg 201 Reference to the fourth Doctor.
"I admit that at some point I'd like to be really handsome." He will, in his eighth and tenth incarnations.
Pg 241 "UNIT put them away in one of their super-security prisons, and I suppose they're still there." Battlefield.
Pg 249 "Artron energy." First mentioned in The Deadly Assassin.
Pg 275 "This last one, I visited your moon. Also, my own mind." Timewyrm: Revelation.
Pg 276 "Sometimes I wish I could have my memory wiped clean. Start fresh." He will, but not until The Ancestor Cell.
Pg 272 "She promised to visit him often and she did, always the same while he grew older, always acting as if she'd seen him only yesterday, which was sometimes the case." This is very reminiscent of the conclusions of Timewyrm: Revelation and Happy Endings.
OLD FRIENDS AND OLD ENEMIES
UNIT, though nobody familiar, aside from the Brigadier.
The Doctor's house on Allen Road also appears, having been seen in a number of NAs and comics.
NEW FRIENDS AND NEW ENEMIES
Ethan Amberglass, although he's in a coma by the story's end.