You can only have one....

https://web.archive.org/web/20140708093123/http://www.chesscafe.com/text/review756.pdf

Spielman's "The Art of Sacrifice in Chess".

I am not confident that it is a good idea to base a library on if-you-can-only-have-one books. There is a certain cost in the attempt to cover a bunch of topics in one book. In case you are willing to consider books with a narrow focus, here are some reading possibilities that I often mention:
Simple Attacking Plans by Fred Wilson (2012)
https://web.archive.org/web/20140708090402/http://www.chesscafe.com/text/review874.pdf
http://dev.jeremysilman.com/shop/pc/Simple-Attacking-Plans-77p3731.htm
Logical Chess: Move by Move by Irving Chernev (1957)
https://web.archive.org/web/20140708104437/http://www.chesscafe.com/text/logichess.pdf
The Most Instructive Games of Chess Ever Played by Irving Chernev (1965)
https://chessbookreviews.wordpress.com/tag/most-instructive-games-of-chess-ever-played/
Winning Chess by Irving Chernev and Fred Reinfeld (1948)
https://web.archive.org/web/20140708093415/http://www.chesscafe.com/text/review919.pdf
Back to Basics: Tactics by Dan Heisman (2007)
https://web.archive.org/web/20140708233537/http://www.chesscafe.com/text/review585.pdf
https://www.chess.com/article/view/book-review-back-to-basics-tactics
https://static1.squarespace.com/static/5856bd64ff7c50433c3803db/t/5895fc0ca5790af7895297e4/1486224396755/btbtactics2excerpt.pdf
Discovering Chess Openings by GM John Emms (2006)
https://web.archive.org/web/20140627114655/http://www.chesscafe.com/text/hansen91.pdf
Openings for Amateurs by Pete Tamburro (2014)
http://kenilworthian.blogspot.com/2014/05/review-of-pete-tamburros-openings-for.html
https://chessbookreviews.wordpress.com/tag/openings-for-amateurs/
https://www.mongoosepress.com/catalog/excerpts/openings_amateurs.pdf
Chess Endgames for Kids by Karsten Müller (2015)
https://chessbookreviews.wordpress.com/tag/chess-endgames-for-kids/
http://www.gambitbooks.com/pdfs/Chess_Endgames_for_Kids.pdf
A Guide to Chess Improvement by Dan Heisman (2010)
https://web.archive.org/web/20140708105628/http://www.chesscafe.com/text/review781.pdf
Studying Chess Made Easy by Andrew Soltis (2009)
https://web.archive.org/web/20140708090448/http://www.chesscafe.com/text/review750.pdf
Seirawan stuff:
http://seagaard.dk/review/eng/bo_beginner/ev_winning_chess.asp?KATID=BO&ID=BO-Beginner
http://www.nystar.com/tamarkin/review1.htm
https://web.archive.org/web/20140627132508/http://www.chesscafe.com/text/hansen173.pdf
https://www.chess.com/article/view/book-review-winning-chess-endings
https://web.archive.org/web/20140708092617/http://www.chesscafe.com/text/review5

"Remember, if you like books--like reading them and owning them--there's no such thing as 'one chess book.' ... as you acquire one or two and read them through--even if you don't--you'll find yourself drawn to the chess section every time you walk into Walden's or Barnes and Noble or Borders. If you leaf through the books and compare their contents to what you need, you'll soon find yourself dedicating a shelf or two of your bookcase to chess books. You'll want to have all of Sierawan's books (as soon as they're back in print). You'll yearn to complete your collection of Alburt's series. You'll start haunting used book shops for old copies of Fischer's 'My 60 Memorable Games.' Your hair will gradually grow unkempt, and a distracted wild look will creep into your eyes. If you're separated from your books for too long, your hands will begin to twitch and you'll start plotting knight moves across the checkered tablecloth at the Italian restaurant where you're supposed to be wooing your wife / girlfriend. You've entered a perilous zone ... 'Chessbibliomania' is not a condition to be easily dismissed, and research has shown it isn't curable. Maybe you'll be better off just buying a gin rummy program for your computer and avoiding this chess book madness altogether. Happy reading!!"
http://groups.google.com/group/rec.games.chess.misc/msg/d96eccf5ddec3c33

It just occurred to me reading this thread, I do not have any chess books. For real. I used to, but I traded them in at the bargain bin used book store. Now I just have a stash of videos that I watch once in a while when an Opening interests or annoys me.

So if I could just take one chess book, I'd use the slot for another genre like fantasy or sci-fi.

For one book only, that's a pretty good choice...

The Mammoth Book of the World's Greatest Chess Games by Burgess, Emms & Nunn...

https://www.amazon.com/Mammoth-Worlds-Greatest-Chess-Games/dp/1849013683/ref=sr_1_1?crid=1VEAYJD75MG2B&keywords=mammoth+book+of+the+world%27s+greatest+chess+games&qid=1569789766&s=books&sprefix=mammoth+book+of+the+wor%2Caps%2C211&sr=1-1

More choices...

Good Chess Books for Beginners and Beyond...

https://www.chess.com/blog/RussBell/good-chess-books-for-beginners-and-beyond

aka "Spongey"...

My choice would be Bronstein’s Zurich 1953.

Another excellent choice!

Thank you, Russ. Actually, when I “permanently” gave up chess 20-something years ago, this was one of 3 books that I couldn’t bear to part with while giving my collection away. The others were the hardback first edition of Fischer’s 60 Memorable Games and Tal’s marvelous book on the 1960 WC match.

Those were/are great books to retain!  I have all the exact same books as well!