The Laundry Files is a series of novels by British writer Charles Stross. They mix the genres of Lovecraftian horror, spy thriller, science fiction, and workplace humour. Their main character for the first five novels is "Bob Howard" (a pseudonym taken for security purposes), a one-time I.T. consultant turned occult field agent. Howard is recruited to work for the Q-Division of SOE, otherwise known as "the Laundry", the British government agency which deals with occult threats. "Magic" is described as being a branch of applied computation (mathematics), therefore computers and equations are just as useful as, and perhaps more potent than, classical spellbooks, pentagrams, and sigils for the purpose of influencing ancient powers and opening gates to other dimensions. These occult struggles happen largely out of view of the public, as the Laundry seeks to keep the methods for contacting such powers under wraps. There are also elements of dry humour and satirisation of bureaucracy.

While the stories are partially inspired by the Cthulhu Mythos universe created by H. P. Lovecraft and others, they are not set in Lovecraft's universe. In Stross's world, the greatest magicians are the scientists who closely study the phenomena; it features a secret history of historical thinkers who also dabbled in or stumbled upon occult uses of their work.

The Concrete Jungle and Equoid both won the Hugo Award for Best Novella, and "Overtime" was a nominee for best novelette. The series as a whole was nominated for the Hugo Award for Best Series in 2019 and 2024.

The Atrocity Archives is the first collection of Laundry stories by British author Charles Stross. It is set in 2002–03 and was published in 2004. It includes the short novel The Atrocity Archive (originally serialised in Spectrum SF, #7 November 2001) and The Concrete Jungle, which won the 2005 Hugo Award for Best Novella.

The protagonist of both stories is computer expert Bob Howard, who re-discovers certain mathematical equations that contact other worlds. The Laundry detects the disturbance and swoops in to give him a mandatory job offer ("I thought I was just generating weird new fractals; they knew I was dangerously close to landscaping Wolverhampton with alien nightmares"). From his position in the Laundry, a secret British occult intelligence organisation, Howard is allowed to learn something of the secret history of the world, as well as the various modern counter-measures the Laundry has adopted to deal with these threats. Despite the nature of the work, the Laundry is an efficient and low-key modern organization; more cubicle-jockeying than stately mansion towers and hidden volcano lairs, in other words. A tag-line used for the books by publisher Ace Books was "Saving the world is Bob Howard's job. There are a surprising number of meetings involved".

In The Atrocity Archive, Howard is given work as a field agent in finding and protecting Irish Professor of Logic Dominique "Mo" O'Brien, as her work – dangerously close to the point of bending reality – has triggered the Laundry's person-of-interest checks. There, Howard must contend with the Black Chamber, which in this setting was never actually disbanded, but merely went underground as the US government's equivalent of the Laundry. Howard and Mo eventually head to Amsterdam and deal with Middle Eastern terrorists also on the hunt for Mo's work. They also research the Atrocity Archive, a classified record of German efforts in World War II. In this universe, the Thule Society, a pagan and occult group formed during the defeat of Germany in World War I, actually achieved results; they were absorbed by the Ahnenerbe, which became the occult branch of the SS, and who used German mathematician David Hilbert's research (unwillingly) to attempt to gain an edge for the Nazis. The Wannsee Conference was thus an attempt to harness the occult via mass human sacrifice in the Holocaust, but it ultimately failed after Allied interference. Mo is captured by the terrorists and sent via wormhole to an alternate universe where the Nazis did succeed – although not in a manner they would have preferred. In this alternate universe, the Nazis summoned a frost giant out of Germanic/Norse legend, which was actually an elder being that fed on heat and who proceeded to destroy Earth. Bob and a team of SAS agents open their own gate, infiltrate the frozen universe, rescue Mo, and leave a nuclear bomb to 'sanitise' the scene. Bob belatedly realises that the nuclear bomb is a counterproductive trap; the frost giant intends to use its power to propel it into their reality, which has far more heat to eat. Bob manages to stop the device from exploding before escaping back to his original universe.

In The Concrete Jungle, Bob Howard is called in for an emergency: there are too many Concrete Cows in Milton Keynes. Howard reads classified files on the presumed cause: gorgonism, which has been banned by treaty for military use, and has been researched by various scientists over time – Lavoisier, Geiger, and Rutherford. Alarmingly, the government has built a network to artificially emulate gorgons in FPGAs, then planned a network of cameras that could be hooked into this emulation – the CCTV network of anti-crime cameras deployed across Britain in the late 90s and early 2000s. This network was intended as a defense if the Old Ones were to rise and attack; however, someone has subverted a CCTV camera to stone a cow, then deposited it with the other concrete cows. As unauthorised use of the CCTV-basilisk network could hold the entire nation at hostage, this is an incredible risk. In an unrelated event, Howard is informed that he is being negligent about preparing for a meeting about a Business Software Alliance audit for the Laundry's software; Howard strongly opposes the audit, as the BSA invariably installs "spyware" to snoop for unauthorised installations.

Howard, with the assistance of Detective Inspector Josephine Sullivan of Milton Keynes, investigates the incident, which soon expands to the murder of humans as well as cows. They attempt to track who could possibly have had access to the gorgon-emulation software and installed it. Meanwhile, a ransom note is received demanding the software be uninstalled. Their investigation eventually leads them to the developers of the software, who are mostly dead from their own cameras, and an agent named "McLuhan" ("the medium is the message"). Howard discovers that the whole incident was inter-department wrangling gone wrong; a rival manager had been seeking to show that Angleton (Howard's manager) was incompetent and letting his own secret programs leak, and her minions had covered their tracks more bloodily than necessary. The "BSA audit" had been an excuse to install the gorgon-software into the Laundry's own internal cameras while Angleton was distracted. Howard and Sullivan infiltrate the Laundry to pull its Internet connection, while Angleton attends the meeting where he might be deposed. Howard comes upstairs to find Angleton victorious; it seems that his rival did not understand who Angleton truly reported to in the matrix management of the Laundry before launching her attempt to have him dismissed. His position as head of Counter-Possession Unit was actually secondary to his position as Private Secretary, and that position's manager went all the way to the top.