Fantasy/Detective series written by Creator/RandallGarrett in the 1960s and 1970s, set in an AlternateHistory with two major branches from our own:

# King [[RichardTheLionHeart Richard the Lionheart]] survived the crossbow wound that killed him in our history, but the narrow escape caused him to reconsider his life and become a famously great monarch. Nobody ever got around to agitating for Magna Carta, and in the twentieth century the Plantagenet dynasty still rules absolutely in England -- not to mention France, most of the rest of western Europe, and North and South America.
# The course of scientific discovery went down a different path, with the result that magic and psychic powers are well-understood phenomena with clearly-defined rules (but nobody knows much, or cares, about the physical sciences).

As a result, in the 1970s, the Angevin Empire's society and technology largely resembles those of, to pick a comparison ''entirely'' at random, the Franchise/SherlockHolmes stories. But with wizards.

Lord Darcy is an official investigator for His Highness the Duke of Normandy, solving mysteries too weird or too politically sensitive for the normal police to handle. He is ably assisted by Master Sorcerer Sean O Lochlainn, a one-man magical CSI department.

In the later stories, Lord Darcy and Master Sean increasingly often become entangled in the espionage and counter-espionage of their world's version of the ColdWar, between the Angevin Empire and the ambitious-but-not-strong-enough-to-wage-conventional-war Polish Empire.

Lord Darcy was introduced in 1964. ''Murder and Magic'' (1979) and ''Lord Darcy Investigates'' (1981) collect all of the Lord Darcy stories, bar two that were published later. Garrett also wrote one Lord Darcy novel, ''Too Many Magicians'' (1966), which fits between. A 2002 omnibus edition collects all three books and the two stray stories.

In the 1980s, following Garrett's death, his friend and fellow-author Creator/MichaelKurland wrote two more Lord Darcy novels, ''Ten Little Wizards'' (1988) and ''A Study in Sorcery'' (1989).
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!!The series provides examples of:

* AllohistoricalAllusion: In one of Kurland's novels, a character views paintings of Plantagenet monarchs past, and speculates about how horribly history could've gone, had King Richard died sooner and the throne had passed to his JerkAss brother instead of his nephew.
* AlwaysMurder: Well, mostly. Subverted in one story, where it turns out they already know what the victim died of, and just need Darcy to figure out where he'd hidden an important document before he snuffed it.
* AssholeVictim: Very much so in "The Eyes Have It"
* TheBaroness: Olga Polovski, Agent 055 of the Polish Secret Service.
* BlackMagic
** Combined with SaintlyChurch, in that performing any kind of harmful deed through magic (even injuring a criminal in defensive combat) causes [[ThisIsYourBrainOnEvil irreparable mental damage of some sort]]. The clergy function as a sort of magical psychologists, though they can't "cure" people of the resulting ([[NotBrainwashed or causative!]]) evilness, they can magically detect psychosis and render such people [[BroughtDownToNormal incapable of working magic]] to prevent further harm to a black magician's mind. As a result, practicing magic requires an official license gained through examination by the clergy.
* BlueBlood
* BrilliantButLazy: The Marquis of London.
* ClarkesThirdLaw: Inverted. There are instances of devices that work on clearly understood principles, in our world, but in the Darcy world, their sages have no idea ''how'' they work, just that they do. Examples include the teleson (a telephone), and a device created by a top secret military research program: a flashlight.
* ClearTheirName:
** In "The Bitter End", Master Sean is accused of the murder by the bumbling [[Franchise/ThePinkPanther Sergeant Cougair Chasseur]].
** Master Sean is also accused of the murder in ''Too Many Magicians'', but it's only a ploy by the Marquis of London to get Lord Darcy to come and investigate the murder for him.
* CombatClairvoyance: Lord Commander Ashley, in ''Too Many Magicians'', has just a touch of magical talent that gives him the occasional burst of prescience. The most dramatic presentation of this power comes when he's fighting an opponent armed with an enchanted sword that's effectively invisible; Ashley's power lets him accurately predict the other man's movements.
* DeadMansChest
* DeadPersonImpersonation: In [[spoiler:"The Muddle of the Woad"]]
* DetectiveMole: In [[spoiler:''Too Many Magicians'']]
* EnsignNewbie: Lieutenant Darcy is a self-acknowledged one in "The Spell of War", learning from his SergeantRock.
* EverybodyDidIt: Proposed and then shot down in "The Napoli Express", in a fairly obvious critique of ''{{Murder on the Orient Express}}''.
* EyeRemember: in [[spoiler:"The Eyes Have It"]]
* FakingTheDead: In [[spoiler:Michael Kurland's ''A Study in Sorcery'']]
* FantasticCatholicism
* ForWantOfANail: The discovery that led to the harnessing of magic is presumably, ''somehow'', a consequence of Richard the Lionheart's survival. (It might be easier to imagine a timeline in which Richard's survival was a consequence of the harnessing of magic, but it's explicitly stated that in this timeline Richard's survival came first.)
** The explanation is that Richard's brush with death caused him to change his rulership style. For the remainder of his reign, he encouraged learning and the arts. And this trend continued under his successor; his nephew Arthur. It was the academic environment fostered by Richard and Arthur that led to the discovery of the rules of magic.
* FunctionalMagic
* FunetikAksent: Polish characters who aren't trying to disguise themselves as Angevin subjects tend to have this.
* GentlemanWizard: Several minor characters (including a couple of victims). Recurring character Lord John Quetzal is an interesting case, as he's a nobleman and a gentleman, but he's from the colonies (Mexico, in our version of reality), which gives him some interesting quirks
* GreatDetective: both Darcy himself and the Marquis of London.
* IntrinsicVow: The King's Messengers all take one to never reveal an official message to anyone but the intended recipient. It's backed up by a magical compulsion to die rather then reveal it.
* IstanbulNotConstantinople: Especially when it comes to the Americas.
* ItWillNeverCatchOn: In one story, a wizard speaks disparagingly of a folk superstition that [[ThatOldTimePrescription wounds can be treated with a kind of mould]]. In another, a man engaged in chemical research is regarded as a time-wasting eccentric (although Darcy, at least, thinks he's on to something).
* TheLawsOfMagic The series could practically serve as a textbook on the subject.
* LockedRoomMystery: At least half the series. Notably, in spite of the obvious temptation, the answer is ''never'' "AWizardDidIt".
* MagicAIsMagicA
* MagicCompass: In one story, Master Sean enchanted a splinter left behind by a murder weapon and used it to find the rest of the weapon.
* MajoredInWesternHypocrisy: Several instances, though all without the hypocrisy part because the Angevin Empire is better than its counterparts in our world. The most prominent example is Lord John Quetzal, a native American nobleman who is studying in London in ''Too Many Magicians''. The "character wrong-footed by foreigner's education" version appears in Michael Kurland's ''A Study in Sorcery'', where Lord Darcy meets a woman who has invented a dramatic past for herself that includes a stint in the harem of the son of the Osmanli Sultan; in the course of dissecting her story, he mentions that he and the son of the Osmanli Sultan were at Oxford together.
* MimingTheCues: In "The Napoli Express" a murder is committed while Lord Darcy is undercover, leaving him unable to take official charge of the investigation. While another detective leads the investigation with Master Sean's assistance, Lord Darcy uses hand-signals to prompt Master Sean to suggest "what Lord Darcy would do next if he were here".
* MindOverManners
* ModernMayincatecEmpire: Garrett left the state of things in the Americas largely undefined, but ''Too Many Magicians'' mentions that the Aztec emperor Montezuma's descendants now rule "Mechicoe" as noblemen of the Angevin Empire. Michael Kurland's ''A Study in Sorcery'', being set largely in North America, is much more specific, and adds that part of the Aztec Empire continues unabated farther south.
* MrExposition: Master Sean, who's a teacher when he's not helping bust criminals, has a tendency to accompany every forensic test he does with an explanatory lecture. Lord Darcy encourages him, even when [[AsYouKnow he's seen this test done before]], because [[JustifiedTrope the lecture is never exactly same, so there's always a chance to learn something]].
* TheNeidermeyer: The commander of Darcy's unit in "The Spell of War".
* NoodleIncident: In "Too Many Magicians", a few of Darcy's unseen cases are mentioned in passing, but nothing more is revealed about them. Similarly, at least one case mentioned by a FanBoy in "Ten Little Wizards" is not covered in the extant stories.
* OriginsEpisode: "The Spell of War", one of the last-published stories, recounts the first meeting of Lord Darcy and Master Sean on a battlefield during their world's equivalent of World War II.
* OnlyOneName: Lord Darcy's given name is never revealed.
** In "The Spell of War" (where he's not yet inherited his title), he's referred to as "Lieutenant Darcy".
* OrientExpress: "Murder on the Napoli Express" is set on the Angevin Empire's counterpart to the famous train.
* PhoneInDetective: The Marquis of London (an {{Expy}} of NeroWolfe)
* PoirotSpeak: Played with in "The Bitter End", which is set in Paris and features the alternate universe version of [[Franchise/ThePinkPanther Inspector Clouseau]].
* RichardNixonTheUsedCarSalesman: In a world where the automobile was never invented, Ferarri of Milan is a noted manufacturer of firearms.
* RoyalWe: King John IV uses this when speaking as King-Emperor and drops it on those rare occasions where he needs to speak man to man.
* SaintlyChurch: Apparently magic makes it possible to ensure that only suitable people become priests (and has presumably cleared up the whole is-there-a-God question, although that point is never really addressed).
* SerialKillingsSpecificTarget: The ultimate target in ''Ten Little Wizards''.
* ShoutOutLiterature: Various stories guest-star alternate universe versions of other famous detectives and secret agents, not to mention one or two other SF writers.
** One example is found in the novel ''Too Many Magicians''. My Lord the Marquis of London is an [[NeroWolfe enormously fat man]] who grows orchids and leaves all the foot work to his assistant Lord Bontriomphe.
* SmokingGunControl: A character once comments that detective work in cities would be a lot easier without all the anti-scrying spells placed on homes and businesses. Darcy comments that if these were not there, detective work would be non-existent - you could just call in a journeyman sorcerer to use some basic divination spells and the case would be solved in under an hour. He also mentions that this would also eliminate all hope of personal privacy, as any interested mage could scry into your house or office whenever they wanted (This is the reason that anti-scrying spells are placed on homes and businesses in the first place).
* SpellConstruction: altough magic is limited to those with the talent, actually casting a spell requires intricate and specific ingredients and actions.
* TheStarsAreGoingOut: In "The Ipswich Phial", a top-secret magical effect makes Father Lyon ''think'' this has happened, by causing a sort of hysterical blindness in a localized area.
* StealthPun: The infamous subplot in ''Too Many Magicians'' involving the uncle from the Isle of Man.
* SummationGathering: Most notably in ''Too Many Magicians'', but also in several of the other stories.
* SufficientlyAnalyzedMagic: a key element to the whole series.
* ThatOldTimePrescription: The superstitious folk remedies mentioned above under "It Will Never Catch On" are of this type.
* ThrillerOnTheExpress: ''The Napoli Express''
* TrappedByGamblingDebts: happens to one character in ''Too Many Magicians''.
* {{Tuckerization}}: Creator/MichaelKurland gets name-checked several times in various stories, and the greatest wizards of the Angevin Empire include Sir Lyon Gandolphus Grey (Creator/LSpragueDeCamp by way of Creator/JRRTolkien), Sir Edward Elmer (Creator/EEDocSmith), and Sir James Zwinge (Randall James Zwinge, aka The Amazing Randi).
* TwinTelepathy: A minor plot point in Michael Kurland's ''A Study in Sorcery''.
* {{Uncoffee}}: Referred to instead as "caffe".
* UnfriendlyFire: In "The Spell of War", Darcy, a young officer at the time, chooses not to notice that the commander of his unit--who'd been a tyrant and endangered the men--had a low-angle bullet entry wound from a pistol... received while under fire from a sniper who was using a rifle from a high angle. (The soldier who killed him died almost immediately afterward, while the one piece of evidence--the body--is destroyed in an artillery barrage; Darcy chooses to [[ThePowerOfLegacy protect the soldier's reputation]].)
* UtilityMagic
* WitchSpecies: In order to practice magic, one must be born with "the Talent". This exists to varying degrees, such that only a small portion of the population can work magic, some others exhibit strange powers, nearly all can at least perceive strong magic to some extent, and a few on the other end are magically inert and utterly unable to directly sense the supernatural.
** Interestingly, the world's foremost magical theorist and expert in the symbolic manipulations underlying modern magic happens to be unable to work magic at all.
* WorldOfPun: Not at the pun-per-paragraph extreme, but the series definitely keeps the punometer ticking away.
** Especially when it comes to the literary shout-outs, which are often veiled behind the French equivalent of CanisLatinicus, as with master-spy James le Lien[[note]]"lien" = "[[Literature/JamesBond bond]]"[[/note]], or the sedentary Marquis of London's invaluable assistant, Lord Bontriomphe[[note]]"bon triomphe" = "[[NeroWolfe good win]]"[[/note]].
** Also, one story has the local policeman suggest that the victim was attacked by a demon or fire elemental; Master Sean soon disproves the hypothesis, and it seems to have been thrown in largely as an excuse to have somebody say "Elemental, my dear Doctor".
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