Bob Howard, Laundry hacker newly promoted to field agent, finds himself protecting a logic professor from rogue SS-Ahnenerbe agents who’ve been hiding in another dimension since the end of the War. But their biggest problem is the frost giant that was summoned. And later there’s the subverted CCTV cameras with the basilisk stare.
To borrow Charlie Stross’s own words from his Crib Sheet:
So there you’ve got the ingredients. Lovecraftian horror; the secret agency [the Laundry] dedicated to protecting us from the scum of the multiverse: the protagonist (Bob, a put-upon hacker who is an utterly inappropriate hire but who can’t be gotten rid of): the cold war ambiance: the dark humour. I probably ought to mention the novels of Len Deighton, which I was re-reading at the time—one of the most significant of the British cold war thriller writers.
Elsewhere, he makes the half-serious point that Deighton was a horror writer—the existential crisis of the Cold War—while Lovecraft was a spy writer.
Stross piles horror upon absurdity in a satisfying and original creation.