There is a time machine causing dangerous instabilities, fracturing people both mentally and physically. Worse, its continued use might see the time continuum chewed up and spat out. The Doctor turns to his sometime ally, sometime enemy Sabbath for help tracking down the machine and along the way discovers some very disturbing things about where his heart lies in the matter…
Tropes present in Camera Obscura include:
- Anthropomorphic Personification: of Death. Probably continuing on from the NAs.
- Badass Boast: See the page quote for the series as a whole.
Break, damn you! Break! You've never had a spanner like this thrown in you! Chew on me till your teeth crack. Grind me up till your gears lock. I'm the nail in your tyre, the potato jammed in your exhaust pipe, the treacle poured in your petrol tank. I'm the banana peel beneath your foot, the joker that ruins your straight flush, the coin that always comes up heads and the gun you didn't know was loaded. I am the Doctor!
- Body Horror: Happens to the Doctor quite a lot for one book. First he gets his heart ripped out, then he gets squashed flat by a falling sandbag.
- End of the World as We Know It
- Gorn: To go along with all of the Body Horror inflicted on the Doctor, it's all described in pretty graphic detail.
- Heart Trauma: After Sabbath rips the Doctor's second heart out of his chest in The Adventuress of Henrietta Street, he finds out that Sabbath has placed it in his own chest to use as a navigating tool of some sort.
- Humanoid Abomination: Nathaniel Chiltern is split into two unequal parts, the second of which ends up fused together with an electric toaster and a rosebush as a result of a failure in the time machine to work properly.
- Ill Girl: The Doctor's erm, heart condition leaves him frail and prone to fainting.
- Organ Theft: See Heart Trauma above.
- Sim Sim Salabim: Anji, being South Asian, stands out pretty heavily in Victorian London, and as a result, finds it easiest to wear a sari and not speak to anyone while the three of them are staying, capitalizing on the peoples' assumptions about India of the time. Needless to say, she doesn't particularly enjoy this trip.
- Split Personality: Constance Jane, a "fake" psychic, has this problem, as well as an ability to sense time anomalies. Octave, the magician who tries to kill the Doctor, has an inversion: his use of the faulty time machine split him into eight separate bodies, each of which has the same sensory input and feelings as all of the others.
- Time Machine: A damaged and incredibly destructive one is the cause of most of the plot.
- Victorian London: Where the book takes place.
- Victorian Novel Disease: See Ill Girl. Everyone assumes the Doctor is consumptive.