THERE IS THIS THING ABOUT MATHEMATICIANS AND PROGRAMMERS: they come in several flavors, often overlapping, but with distinct strengths and weaknesses specific to each type.

Alex’s talents are multivariate and recondite, but he has a particular aptitude for language lawyering. That is, he takes great delight in exploring the nooks and crannies of formal languages and understanding how and in what circumstances they exhibit side effects or anomalous behavior that a naive or inexperienced programmer would not expect.

Alex is also very intelligent. He is under Basil’s control, but he is not happy about his long-term survival prospects if this situation persists. Especially as his entire face is on fire and it feels as if his nose will fall off if he sneezes. Basil is not, in Alex’s estimate, an entirely thoughtful employer: certainly he is unlikely to prove as accommodating or merciful as the Laundry’s HR department.

Alex cannot disobey Basil’s direct order. But he can creatively interpret the instructions he has already been given. And he cannot help but overhear what Basil is saying next door.

And it occurs to him that when Basil said, “. . . stand by the door and kill anybody who comes through it,” Basil didn’t specify which direction they had to be going in.

In the normal state of affairs, a fight between a highly trained soldier from the Territorial SAS and a pencil-necked geek will tend to end with a de-leaded geek. But in the interests of rebalancing the equation, the highly trained soldier has just handed his principal weapon to the vampire overlord who has turned him into a shambling robot whose motivation is the overriding order to turn out the bloody lights rather than defending himself. And the pencil-necked geek is a fully juiced-up young vampire who has rules-lawyered himself around to some very interesting conclusions about his own freedom of action within the constraints Basil specified, and who is extremely pissed off right now because he has third-degree burns across most of his face.

Alex isn’t stupid. He lets the soldier pull the circuit breaker, and then he tries to kill him.

• • •

I DON’T REMEMBER THE NEXT BIT TOO CLEARLY.

The light flickered and something of its quality changed: it reddened, or lost something from the blue end of the spectrum.

There was a scream, and the nightmare figure turned towards the doorway and raised its gun. That’s when I began to turn, and raised my camera, and pushed the shutter release immediately: not even aiming at him, just relying on the firmware to lock onto the person-shaped object closest to the center of the focal area and do the rest.