''The Fear Index'' is a 2011 book written by Robert Harris.

Taking place over the course of a single day, we follow the story of Dr Alex Hoffmann, an American owner of a multi-billion dollar hedge fund company currently living in Geneva. He's on the verge of creating a powerful automated algorithmic system which will manage the hedge fund, making the company billions. However, the night before investors are allowed to see the new system, Alex's once-ordered life starts to unravel.

It all started innocently enough; a mysterious rare first edition copy of UsefulNotes/CharlesDarwin's ''The Expression of Emotions in Man and Animals'' appears through the post. However later that evening an intruder breaks into his house, knocks him unconscious and things unravel from there.

Note that due to the very nature of the book it's rather hard to discuss many aspects without ruining it. You have been warned.

!!Provides Examples of the Following Tropes;

* [[spoiler: AIIsACrapshoot]]: Alex at the end sees the whole book a form of experiment, however its more likely [[spoiler: VIXAL-4]] was just trying to get rid of the only man that could possibly predict what was going on.
* AssholeVictim: Lets face it Hoffmann starts out like this. He's a multi-billionaire hedge fund manager (which most people will just translate as "banker") who comes off cold and uncaring to everybody. He does soften, slightly, as the book advances.
* BeAsUnhelpfulAsPossible: Quarry, but that's just because he's trying to protect the money making algorithm.
* CluelessChickMagnet: Hoffmann.
* DespairEventHorizon
* BigFancyHouse: Hoffmann's house which costs sixty million dollars.
* EverythingIsAnIpodInTheFuture: Hoffmann Investment Technologies is described like this. Everything is handled on computers and sleek computer devices; to the point where having anything paper is against company policy.
* EverythingIsOnline
* FacialRecognitionSoftware: Used as a security measure to get in and out of Hoffmann Investment Technologies. Funnily enough it requires the person to show no emotion.
* [[spoiler: {{Gaslighting}}]]: Which slowly makes Hoffmann completely unhinged by the end.
* InspectorJavert
* [[spoiler: TheKillerBecomesTheKilled]]: The man that broke into Hoffmann's house.
* NeverSuicide
* NoPaperFuture: Enforced in universe. However, Hoffmann himself collects rare books. And of course all the money in the book is dealt with electronically.
* NotWithThemForTheMoney: Gabriel who is actually getting a bit sick of all the money.
* PiecemealFundsTransfer: Averted, as you would expect from a book focused around instantaneous trading.
* RippedFromTheHeadlines: The stock flux at the end of the book actually happened.
* ShoutOut: The story takes place in Geneva, [[spoiler: the original home town of Doctor {{Literature/Frankenstein}}]]
* [[spoiler: SinisterSurveillance]]: Alex discovers this near the end of the book. Gabriel sees this and gets the wrong idea.
* SpotOfTea: Joked with where Leclerc says he better have tea in an interview with Quarry.
* TwentyMinutesIntoThePast: Set on the 6th of May 2010.
* YouHaveToBelieveMe