!!The books:

* CompleteMonster: See [[Monster/JackReacher here]].
* FridgeBrilliance: As a general rule, Reacher is in peak physical condition and at the top of his game. Which doesn't make sense, because he's technically retired. But he's naturally built very strongly, spends his days wandering about the country, sees action every time a story comes up, and and sometimes this is actually explicitly noted as not being enough.
* FridgeHorror: At the end of ''Nothing To Lose'', Reacher and his partner blow up [[spoiler:the metal salvaging plant owned by the villain and his co-conspirators]] with their own bomb. It's poetic justice... until you consider that one of the side plots was [[spoiler:the presence of a highly carcinogenic chemical and how small amounts of it are leeching into the water supply]] not to mention the main plotline that [[spoiler:the villains were building a dirty bomb packed with depleted uranium]]. Congratulations, Reacher, for creating an environmental disaster site.
* MartyStu: Reacher can tend this way at times - it's particularly pronounced in those volumes of the series which are written in first person.
* {{Padding}}: Child can get pretty obsessive about cataloging every single facet of a character's appearance, or a room, regardless of anything important to the story.
* RomanticPlotTumor: Reacher's romances with the GirlsOfTheWeek are not exactly the most intriguing part of the series.
* TearJerker: Reacher, when he finds out the cop and the witness he's befriended in ''61 Hours'' have been murdered. It's one of the preciously rare moments where Reacher genuinely feels despair.

!!The film:

* AlternativeCharacterInterpretation: The accused sniper. Did he [[SummonBiggerFish call Jack Reacher in ]]because EvenEvilHasStandards, as suggested by his partially guilt-driven breakdown upon waking up thinking he committed the crime? Or did he just want to ensure that his framers experienced TakingYouWithMe?
** A bit of Meta-Alternate Interpretation. The book Jack Reacher swaggers around because he's a huge mountain of muscle. By making that character played by Tom Cruise, it comes off more as Jack Reacher is TheNapoleon.
* {{Narm}}: Might be the only time you'll hear someone in a modern film actually say, with no hint of irony, "I'm not a hero. I'm a drifter with nothing to lose."
* NightmareFuel: Werner Herzog as the Zec manages to be completely terrifying despite not really doing anything but talk for the whole film. All he has to do is be himself, the CrazyAwesome director who seriously considered an offer to kill his lead actor, made a film on an active volcano, and ate one of his shoes.
* OneSceneWonder: Robert Duvall as the one guy in the world who can converse on Reacher's level, though technically he appears in at least three scenes.
* TaintedByThePreview: Fans of the books were livid about Tom Cruise's casting, as he looks absolutely nothing like the Reacher of the books (most notably, Reacher is huge, and his size is often an important part of his characterization).
* WTHCastingAgency:
** As stated above Tom Cruise was cast as a protagonist known for being a towering mountain of muscle. Not exactly what fans of the books were expecting.
** ''Creator/WernerHerzog'' plays the BigBad? Though that's probably the IntendedAudienceReaction and more or less what the BigBad was going for.