The Rhesus Chart

Bob Howard, former eldritch IT manager, now field agent and applied computational demonologist and suit-in-training for the no-such-agency called the Laundry, really isn't having a good day. The strain of being involved in Lovecraftian peril isn't helping his marriage – especially when his wife Mo is also a field agent with a combat violin made by Erich Zann. He's barely got a grip on the responsibilities that are headed his way as the newest member of External Assets on "Mahogany Row". And then Andy, another Laundry employee, unleashes Something that requires both Bob and Angleton and a whole mob of zombies… er, Residual Human Resources… to shove back into its hole and seal away.

But hey, at least he's got a pretty harmless side project to work on, processing the Big Data available to the Laundry to detect subtle outbreaks of extradimensional entities. It's currently targeted for vampires, but that's for proof-of-concept. Everyone knows vampires don't exist.

Meanwhile, a brilliant, overworked, and oversensitive programmer named Alex starts running an amazingly complex computer program in the investment group called the Scrum…

With this book, Stross starts the process of adding new viewpoint characters to the series, which until now has been pretty much exclusively Bob Howard's domain with a few interludes of Mo's point of view. There's a reason he'll need new PoV characters, though it doesn't become obvious for a while yet. But it's worthwhile in any case, because the mystery and danger from the Beyond in The Rhesus Chart is something only visible clearly to the reader when they get more than one perspective.

"Everyone knows vampires don't exist" is of course a dead giveaway, especially when it is literally the first line of the novel, that Bob's going to end up running into the closest equivalent to a vampire that the eldritch horror universe Bob exists in can offer. And it turns out that it's a surprisingly close match, just – quelle surprise! – worse than the standard version.

What is a surprise is that the apparent problem Bob faces turns out to only be one facet of a far greater one – that will require a lot more cleverness, and maybe firepower, to solve!

Another surprise in this one is the return of Mhari, Bob's "psycho ex" from the first book. We get a look at her from a different point of view in The Rhesus Chart, and find that – perhaps unsurprisingly – she's not exactly as bad as Bob painted her. Or, possibly, she's worse in some ways, but not in the way we thought.

I'm not going to spoiler other parts of the book; the way things progress is really very much worth finding out for yourself. The ending… well, Bob's got more responsibility, in the worst way.

But the problems in the marriage aren't entirely his, as we'll find out in The Annihilation Score…