Gambit is a Nero Wolfe detective novel by Rex Stout, first published by the Viking Press in 1962.

She was staring up at me. "He's burning up a dictionary?"
"Right. That's nothing. Once he burned up a cookbook because it said to remove the hide from a ham end before putting it in the pot with lima beans. Which he loves most, food or words, is a tossup."

— Archie, explaining Wolfe's reaction to a dictionary that allows the use of "imply" in place of "infer," in Gambit, chapter 1.

A chess prodigy is poisoned during a club tournament, and the police arrest the member who served the victim hot chocolate. Wolfe is hired to exonerate the suspect, but finds that no one else has either an adequate motive or the requisite opportunity.

Gambit employs three distinctive plot elements found in other Wolfe stories. The means by which poison is administered is very similar to the means used in "Cordially Invited to Meet Death". A tape recording is made in an Italian restaurant, one which also appears in "Poison à la Carte". And the part that a gambit plays in a murder echoes "Method Three for Murder".

Sally Blount's father, Matthew Blount, has been arrested for the murder of Paul Jerin, a chess master. Blount had arranged for Jerin to play twelve simultaneous games of blindfold chess at his club. Well into the contest, Jerin complains of physical discomfort and cannot continue. Shortly thereafter, Jerin dies of what tests show to be arsenic poisoning.

During the contest, Jerin had been sitting by himself in a small library off the chess club's main game room. He had nothing to eat or drink except a pot of hot chocolate, brought to him by Blount. After Jerin fell ill, he was diagnosed by a doctor who was playing in the contest; the doctor called for an ambulance but Jerin died at a hospital.

Not only had Blount brought the hot chocolate to Jerin, he had washed out the pot and the cup after Jerin complained that he didn't feel well. Blount is charged with murder.

The only people to enter the library where Jerin sat, other than Blount, were four messengers, who relayed the moves between the main game room and the library. The messengers apparently had no good opportunity to put arsenic in Jerin's chocolate.

Dan Kalmus is Blount's corporate lawyer, and represents Blount after he has been jailed without bail. Blount's daughter Sally is convinced, however, that Kalmus is in love with Blount's wife Anna, and that he won't be inclined to give Blount his best legal efforts. Furthermore, Kalmus' specialty is business law, not criminal law, and he might not have the needed background.

But Sally is certain that her father is innocent, so she hires a reluctant Wolfe to investigate on her father's behalf. Neither Wolfe nor Archie seems to have his heart in the case because the circumstances point so clearly at Blount. And Wolfe learns from the police that their own inquiries discovered no connection between the messengers and Jerin, whereas Blount was unhappy that Jerin had been seeing Sally.

Because none of the messengers could have a motive to kill Jerin, and because he has assumed that Sally is correct that her father didn't, Wolfe conjectures that Jerin was poisoned not because the murderer had it in for Jerin, but to get at Blount, whose apparent motive would surely get him arrested. Wolfe's hypothesis, then, is that Jerin was a pawn, sacrificed in a gambit to get rid of Blount.

Wolfe speaks with each of the messengers as the best alternative suspects, to try to determine which of them might have wanted Blount, not Jerin, out of the way. Each of the four has a possible motive: Sally thinks Kalmus is in love with her mother, Farrow would like to take over Blount's firm, Yerkes wants Blount's vote in a board election but won't get it, and Hausman resents Blount for going easy on him in chess games but winning anyway.

Wolfe learns that there is, in Blount's words, "a certain fact" known only to Blount and to Kalmus that will demonstrate his innocence. The fact turns out to be that Blount really did put something in Jerin's chocolate, but it was sedative in effect, not poisonous. This puts a very different face on things, and as a result Wolfe and Archie, independently, are able to infer both the murderer's identity and how the arsenic got into Jerin.

In most Nero Wolfe novels and novellas, there is at least one unfamiliar word, usually spoken by Wolfe. Gambit contains these three (the page references are to the Bantam edition):

• Trimmer. Page 71, at the beginning of Chapter 8. This word, with this meaning, also appears in Champagne for One.
• Analeptic. Page 125, halfway through Chapter 12.
• Contemned. Page 154, next-to-last page of the book. This word also appears in Prisoner's Base.

• Nero Wolfe — The private investigator
• Archie Goodwin — Wolfe's assistant (and the narrator of all Wolfe stories)
• Matthew Blount — Wealthy businessman, in jail on a charge of murder
• Sally Blount — Daughter of Matthew Blount, and Wolfe's client
• Anna Blount — Wife of Matthew Blount
• Dan Kalmus — Matthew Blount's lawyer, messenger at chess contest
• Charles Yerkes — Banker, business acquaintance of Blount, messenger at chess contest
• Morton Farrow — Sales manager at Blount's company, Anna Blount's nephew, messenger at chess contest
• Ernst Hausman — Retired broker, Sally Blount's godfather, messenger at chess contest
• Victor Avery — The Blounts' family doctor, participant in chess contest

In Gambit, Piotti's restaurant is located on 13th Street, east of Second Avenue (of course, in Manhattan).^[1] In "Poison à la Carte", published two years earlier, the restaurant is on 14th Street, between Second and Third Avenues, thus west of Second Avenue.^[2] Stout was not known for consistency in minor plot matters.

There is a description, in Chapter 3, of the interior of the Gambit chess club. "In a corner was a chess table with a marble top, with yellow and brown marble for the squares, and the men spread around, not on their home squares. The Gazette had said that the men were of ivory and Kokcha lapis lazuli and they and the table had belonged to and been played with by Louis XIV, and that the men were kept in the position after the ninth move^[3] of Paul Morphy's most famous game, his defeat of the Duke of Brunswick and Count Isouard in Paris in 1858,"

In the same chapter, Archie Goodwin tried to guess the next moves of a game that he was watching. After failing every time, he "conceded that I would never be a Botvinnik...."

In Chapter 7, Morton Farrow says, "I'm all right the first three or four moves, any opening from the Ruy Lopez to the Caro–Kann, but I soon get lost. My uncle got me started at it because he thinks it develops the brain. I'm not so sure. Look at Bobby Fischer, the American champion. Has he got a brain?"

Dr. Victor Avery, in Chapter 8, claimed that he didn't hear any conversations during a chess game because he "was concentrating on my reply. I was trying the Albin Counter Gambit. Houghteling had used it against Dodge in 1905^[4] and had mated him on the sixteenth move."

Throughout the story, one of Wolfe's diversions is the reading of Robert Ardrey's African Genesis. This book promulgated the Killer ape theory which claims that humans are naturally murderous.

• Jacques Barzun and Wendell Hertig Taylor, A Catalogue of Crime — There is more detection in this story than in any other of the mulling-and-quizzing sort; here we really see Nero Wolfe's thoughts whirring. Moreover, Archie is in excellent form, and although a chess tournament is a feature, the game itself is not. The great scene is that in which Nero reads and burns the pages of Webster's Dictionary, Third Edition.^[5]
• Nancy Pearl, Book Lust — When Stout is on top of his game, which is most of the time, his diabolically clever plotting and his storytelling ability exceed that of any other mystery writer you can name, including Agatha Christie, who invented her own eccentric genius detective Hercule Poirot. Although in the years since Stout's death I find myself going back and rereading his entire oeuvre every year or two, I return with particular pleasure to these five novels: The Doorbell Rang; Plot It Yourself; Murder by the Book; Champagne for One; and Gambit.^[6]

• 1962, New York: The Viking Press, October 12, 1962, hardcover^[9]

In his limited-edition pamphlet, Collecting Mystery Fiction #10, Rex Stout's Nero Wolfe Part II, Otto Penzler describes the first edition of Gambit: "Blue cloth, front cover and spine printed with red; rear cover blank. Issued in a red, white and black dust wrapper."^[10]

In April 2006, Firsts: The Book Collector's Magazine estimated that the first edition of Gambit had a value of between $150 and $300. The estimate is for a copy in very good to fine condition in a like dustjacket.^[11]

• 1962, Toronto: Macmillan, 1962, hardcover
• 1963, New York: Viking (Mystery Guild), January 1963, hardcover

The far less valuable Viking book club edition may be distinguished from the first edition in three ways:

• The dust jacket has "Book Club Edition" printed on the inside front flap, and the price is absent (first editions may be price clipped if they were given as gifts).
• Book club editions are sometimes thinner and always taller (usually a quarter of an inch) than first editions.
• Book club editions are bound in cardboard, and first editions are bound in cloth (or have at least a cloth spine).^[12]

• 1963, London: Collins Crime Club, April 29, 1963, hardcover
• 1964, New York: Bantam #F2731, February 1964, paperback, .50¢
• 1965, London: Panther, August 1965, paperback
• 1971, London: Fontana, 1971, paperback
• 1973, New York: Bantam #N7697, August 1973,2nd Ed. 1st print, paperback, .95¢
• 1985, New York: Bantam Books ISBN 0-553-14646-7 September 1985, paperback
• 2005, Auburn, California: The Audio Partners Publishing Corp., Mystery Masters ISBN 1-57270-441-1 January 2005, audio CD (unabridged, read by Michael Prichard)
• 2011, New York: Bantam ISBN 978-0-307-76805-6 August 17, 2011, e-book