In the Blood

Online rage as a deadly plague: a collection of clever ideas that fumbles the landing.
Plot summary
This book has an intriguing hook: online trolls are dropping dead, literally killed by their rage. Their anger is a disease spread by the Internet, and an alien octopus is harvesting the rage for their own gain. It caught my eye on the library shelf.
The Doctor and Donna travel the world using human transportation (not the TARDIS), trying to find the source of the anger plague – and to avoid contracting it themselves. They’re accompanied by Fief, an emotionless alien who’s been hired by a media executive to stop the plague. Their business relies on anger and attention, and their customers are dying.
The anger plague is caused by “rempaths”, tiny aliens who causes anger to multiply. (In hindsight, it feels a bit like midi-chlorians.) The anger is being harvested by Gully, an octopoid gangster who the Doctor encountered a previous adventure by the same author. Gully plans to sell the anger into armed conflicts on both sides, because what’s better than angry soldiers?
Donna and the Doctor travel the world sans-TARDIS to track him down, and he’s killed when Fief sacrifies himself. The two of them fall into a tunnel running through the centre of the Earth, where the rempaths are being harvested. (I don’t really understand the ending.)
There’s a side quest where Wilf gets infected, and Donna must find a way to save him.
My thoughts
This book called my eye from the library shelf, and it kept me reading to the end. I found the plot a little unclear, especially the ending, but that might be reflection of how quickly I was reading. (I wasn’t sure if I’d be able to borrow the book, so I was trying to finish it in the library!)
Donna is a good choice of companion for an “anger as plague” storyline, because of Wilf as a calm counterpoint. His infection emphasises the severity of the threat, and feels more meaningful than anonymous people getting hurt. It also creates a nice red herring, where the true solution is more complicated. (Donna overcoming her discomfort with needles, not the blood itself.)
The book hints at some interesting ideas in Time Reaver, the audio story where Gully was introduced. I’m particularly horrified by the idea of a weapon that slows down time for the target, forcing you to suffer more slowly. I’d like to listen to it at some point.
Like most episodes of Doctor Who, this was a fun romp, but I’m unlikely to remember it in the long term.