State of Change
Roots: The name Iam comes from Exodus 3. Peri quotes from Julius Caesar. Anne MacCaffrey's Dragonriders of Pern series, particularly All the Weyrs of Pern. A fair chunk of the plot is reminiscent of The Aztecs.
Goofs: On page 5 the TARDIS exterior is described as an antiquated Police call box, but it's in Cleopatra's Egypt where it's ahead of its time by a couple of thousand years.
It's not strictly a plot hole, but where are the Romans getting their Uranium ore? I'm pretty sure the metal was completely unknown back then.
Why should the Rani assume that the Doctor is alone? Last time she saw him he was travelling with Peri.
Fashion Victims: Not so much a fashion victim, as a reformed one: the Doctor abandons his regular costume for a tunic, cloak, and sandals (though being him, he probably ruins it by wearing the sandals with socks).
Technobabble: Lots of talk about flux tubes and vortex bubbles.
Dialogue Disasters: Peri: 'Is it important?'
The Doctor: 'Only the end of the world.'
Paulinus on the Doctor: 'You're lucky. At least he didn't keep shouting "Haa!" all the time. It's terrible when he does that.'
Dialogue Triumphs: Cleopatra Selene: 'Could've had him fed to the crocodiles.'
Alexander Helios: 'Could I?'
Cleopatra: 'Course. You can do that if you're divine. Probably have to ask mother first.'
Decius: 'I know what I'm here for: money, a pardon, and to avoid having a bird woman spirit-thing rip my throat out one dark night, if I don't co-operate.'
Continuity: The console room contains a Sheraton chair, a Chippendale, a large Chinese pot, a bust of Napoleon, the Ormulu clock, and a massive brass-bound sea chest, which contains [among other things] a 19th Century naval telescope. There is a supply of oil lamps, hurricane lamps, Davy lamps, gas-fuelled lights, electric torches, and synthetic bioluminescents behind a roundel in the console room. The TARDIS swimming pool has adjustable gravity controls. When the TARDIS really runs out of energy, time slows down. The Eye of Harmony provides the TARDIS with both power and a physical and temporal reference point. The manual door control is worked by a crank-handle. There is a miniature camera and microphone on the TARDIS, which will transmit back to the TARDIS.
Peri is aware of some aspects of Roman history, including Shakespeare's version of Julius Caesar.
Some Time-Lords of the first rank have attempted Retro-regeneration (changing into their previous incarnation). In certain circumstances it is possible for a Time Lord to call up the personality and skills of a previous incarnation (as here, and in Timewyrm: Genesys).
The Doctor knows a Venusian nerve pinch. [How does it work on a human?]. He says that his longest-lasting body was his first.
Links: After the last time the TARDIS had power trouble (Vengeance on Varos), the Doctor created a new emergency system - a stand-by mass-converter transforms spare shell material into energy, on an automatic trigger. There are many references to Peri's Transmogrification (Vengeance on Varos). Peri remembers how the Doctor looked when she first met him (Planet of Fire) and events on Androzani (The Caves of Androzani). The Doctor still has some Thal anti-radiation drug (The Daleks) in the TARDIS medicine chest. There are also a number of references to the Rani (The Mark of the Rani). We see brief appearances of the first five Doctors, thanks to the morphic field effect.
Location: Egypt, 41 BC. Alexandria, India, and Rome on Iam's copy of Earth. The bulk of the story happens in 9 or 10 BC, though one page implies it's nearer 11 BC.
Unrecorded Adventures: Peri thinks of her time with the Doctor in terms of 'a few months'. The ceiling of the TARDIS swimming pool is said to have been painted by the same hand that painted the Sistine Chapel. [It's probably an exact replica of Michaelangelo's work.] The Doctor tells Peri to 'remember the molecular cutter', which I don't think we've seen before. The Doctor once studied martial arts in the East [at Det Sen, or with K'Anpo].
The Bottom Line: I really enjoyed this story. Ptolomy's campaign, and the Doctor's fighting tactics are incredibly amusing. The plot is well constructed, and the revelations about the Oracle and Cleopatra Selene are built up extremely well, yet still come as genuine surprises. The whole book is written in a very readable style.