By Lee Child
The Jack Reacher series follows a former US Army Major and Military Police investigator who travels across America with no luggage, no fixed address, and a knack for walking into dangerous situations. Although each thriller works as a standalone story, publication order starting with Killing Floor is the recommended entry point. Four main novels—The Enemy (set in 1990), Night School (1996), The Affair (1997), and The Secret (1992)—are military-era prequels that enrich Reacher's background when read in release order.

New readers should start with Killing Floor. It is the first published Jack Reacher novel and introduces the character clearly without requiring any previous knowledge.
If you watched the TV series first, start with Killing Floor. It is the first Jack Reacher novel and the basis for the first season of the show. After that, continue in publication order unless you specifically want to follow the books connected to each season.
Recommended: For most readers, the best way to read the Jack Reacher books is in publication order, starting with Killing Floor. The books are mostly standalone, but publication order gives the best sense of how the series develops over time.
Publication Order: Publication order is best for most readers because it follows the way the series originally developed.
Chronological Order: Chronological order can be interesting on a reread, but it may reveal background details earlier than intended.
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