* ActorAllusion: Right after Mary Bartowski gets a BigDamnHeroes moment, she tells Chuck and Sarah, "Come with me if you want to live." Mary Bartowski is, of course, played by Linda Hamilton.
* AscendedFanon: Morgan's FanNickname, The Beard, gets referenced several times, most notably in the episode title "Chuck vs. The Beard".
* FakeAmerican: Yvonne Strahovski is Australian, and briefly [[HowsYourBritishAccent uses her real accent]] while Sarah is masquerading as an Aussie.
** Strahovski is actually Polish-Australian; English is her second language. Of course, Sarah spoke Polish in at least one episode.
* HeyItsThatGuy:
** [[Series/{{Scrubs}} Gift Shop Girl]] (after dyeing her hair black) is Chuck's sister.
** [[Series/{{Firefly}} Jayne Cobb]] is an NSA agent!
** Hey, Big Mike sold [[Series/DharmaAndGreg Greg]] a rat!
** [[WhiteCollar Neal Caffrey]] is just one of Bryce's aliases. We later discover that Peter Burke was Sarah's handler.
** [[Series/ArrestedDevelopment Buster Bluth]] and [[Series/{{Dexter}} Vince Masuka]] before him were Buy More assistant managers.
** [[TheDrewCareyShow Oswald]] is a Ring agent.
** [[RockyIV Ivan Drago]] is a Volkoff operative.
*** As if just being there wasn't enough, he even makes at least two {{Shout Out}}s to ''Rocky IV'': "I must break you!" and "If you die, you die."
** [[Franchise/{{Terminator}} Sarah Connor]] is Chuck and Ellie's mom and [[Series/QuantumLeap Sam Beckett]] is their dad.
** Volkoff is Film/JamesBond and [[Series/DoctorWho Rassilon]].
** [[Series/{{Reaper}} The Devil]] is Volkoff's lawyer.
** The character "Greta" is [[Series/AttackOfTheShow Olivia Munn]], [[Series/{{Firefly}} River Tam]], Advertising/TheManYourManCouldSmellLike, and [[Wrestling/{{WWE}} Stacy Keibler]].
** [[SupermanReturns Superman]] is Daniel Shaw.
** [[Series/{{Smallville}} Lana Lang]] is Hannah.
** [[TheMummyTrilogy Imhotep]] and [[Film/{{Daredevil}} the Kingpin]] are FULCRUM agents.
** [[Series/{{Crusade}} Captain Gideon]] is Sarah's dad, while [[Series/BabylonFive Captain Sheridan]] is Devon's.
*** Which makes Chuck's ''Film/{{Tron}}'' poster all the more interesting.
** Chuck has to battle noted HITG Richard Burgi (''Series/TheSentinel, DesperateHousewives, Series/TwentyFour'') to save Sarah. He's also the guy who insulted [[Series/{{Firefly}} Jayne]] and his cunning hat. ("That hat makes you look like an idiot.")
** [[Series/{{Supernatural}} Crowley]] (MarkSheppard) is the Director of the Ring.
** [[VideoGame/MassEffect2 Miranda Lawson and Kal'Reegar]] are Chuck's protectors.
*** And in one episode, [[VideoGame/MassEffect2 EDI]] replaces Miranda and turns out to be a hardass.
*** And [[VideoGame/MassEffect2 Aria]] became a spy.
** Hugo Panzer is StoneColdSteveAustin.
** Casey's former unit featured [[TheExpendables Munroe]] / [[Film/TheDarkKnight Salvatore Maroni]] as the leader, {{Batista}} as TheBigGuy and [[Film/{{Avatar}} Dr. Norm Spellman]] / [[Series/{{Bones}} Colin Fisher]] as the resident CloudCuckooLander.
** [[Series/{{Smallville}} Green Arrow]] needed protecting from his brother in "Chuck Versus the Bearded Bandit". Guess it wasn't a job for Superman...
** Anyone paying attention to NBC's advertising knew that [[Series/{{Community}} Abed]] was going to show up in "Chuck Versus the Hack-off." [[spoiler:Not touted at all? [[ActorAllusion Shirley]], as a Buy More greenshirt with the hots for him.]]
*** Keeping with ''Series/{{Community}}'' references, the same episode features Kick-Puncher as a prison inmate.
** Creator/FreddieWong, as [[TheDanza Freddie]], a fellow hacker.
** Casey Hendershot, ''Series/DeadliestWarrior'' expert, appears twice as a mook. An Iranian villain from "Chuck vs. The A-Team" was (ironically) the lead IDF simulation actor.
** [[VideoGame/TheElderScrollsVSkyrim Ulfric Stormcloak]] shows up in the series finale.
** [[{{Farscape}} John Crichton]] found his way back from the Uncharted Territories and got a job working for Quinn.
** [[{{Lost}} Charlie]] escaped the sub explosion and resumed his career under the alias Tyler Martin.
** Not very many people will get this one, but if you are Canadian and watched Creator/{{YTV}} in the late [=1990s=]/early [=2000s=], you might recognize Lester from [[https://www.youtube.com/watch?v=20ZwSua2wYg this show]]. Unfortunately, the only video on Youtube that just has the intro doesn't have him in it.
* NoExportForYou: Want the show on Blu Ray? You'll have to import the releases from America.
* ScrewedByTheNetwork:
** Rather, "Screwed By The Writers Guild of America" in season 1 - ''Chuck'', whilst not being a major hit, was a surprise hit for NBC & subsequently received a full season order. Unfortunately, this came during the strike & production on the season wasn't resumed when the strike ended.
** Seasons 3 & 4 both received 13 episode orders, before receiving a full season order later on. The problem is that this only happened whilst the intended season finale was in production, leading to the seasons having a somewhat disjointed feel
** In the UK, Sky decided they didn't want to purchase the rights to show the fifth & final season of the show, and as Sky still own the rights to the first four seasons, the fifth season remains unaired in the country as no-one would buy the rights to just the final season of a show - [[ReplacementScrappy but it's okay, because Sky have several new shows that they're sure you'll enjoy]]. Thankfully, the show wasn't in the same situation as ''WesternAnimation/{{Futurama}}'' or ''[[Series/BattlestarGalacticaReimagined Battlestar Galactica: The Plan]]'', where a DVD release was dependent on Sky showing the episodes first & the Season 5 DVD set was released later in the year.
* TruthinTelevision: As in the plot of "Chuck Versus Tom Sawyer", many old arcade games do indeed have a "kill screen" where achieving a high enough level or score can generate bugged levels or cause other unusual effects. However Missile Command is actually ''not'' one of them, and merely loops back to the beginning when a certain point is reached.
** This can be excused, however, if one takes the designer at his word when he says that only he can access the Missile Command kill screen, and that Rush's Tom Sawyer is the "pattern of the universe." The game possibly requires following a particular pattern to access it, which only he knows (and is synced to Tom Sawyer...somehow).
* TypeCasting: Adam Baldwin plays a tough, gruff, trigger-happy, [[FullMetalJacket borderline psycho]] with a [[JerkWithAHeartOfGold good heart]] and [[ICallHerVera a love of guns]]. [[{{Firefly}} Sound familiar?]]
* WhatCouldHaveBeen:
** There was a strong desire to have ChuckNorris appear in an episode.
** The way seasons 3 and 4 were picked up by NBC, with an initial order for 13 episodes, followed by a back 6 and back 11 (respectively) picked up when already in production, affected the way the storylines unfolded. Had the full season orders been made from the start, the first half plot would have extended over the full season instead. The back episodes of both seasons would have then formed the foundation of seasons 4 and 5, respectively.
*** Related to this, Fedak and Schwartz would have explored concepts like Chuck without the Intersect in season 4 more thoroughly (though this did get to be examined in season 5)
** Chuck allows Jill to escape at the end of season 2, complete with a diamond engagement ring used for part of the cover, and her fate is never addressed for the rest of the series. WordOfGod is that she would have been brought BackForTheFinale, but they ran out of time and money for it.
** Actress Natalie Martinez was cast for the pilot in the role of [[http://chuck-nbc.wikia.com/wiki/Kayla_Hart Kayla Hart]], the next door neighbor Chuck was interested in and who would have been a romantic rival with Sarah for Chuck's affections. The development reached the point that Martinez was even present in early promotional photos (see the link) implying that she would be a main character, however she was ultimately dropped before filming of the pilot actually began (in fact, the club Chuck takes Sarah to in the pilot on their date was to have been owned by Kayla, and Chuck took Sarah there specifically to make Kayla jealous). That she was not immediately removed from the cast list afterwards even on the official site led to much speculation and confusion by fans in the show's early history over when she would appear.
** Apparently Devon (Captain Awesome) was supposed to be a limited character who was supposed to turn out to be an enemy operative towards the end of season one. However his popularity led to the idea being dropped and Awesome becoming a series regular. The idea was recycled into Jill and re-recycled into an arc in season 3 where The Ring ''thinks'' Devon is the resident spy in the Bartowski family.
** At one point, the producers were considering bringing [[spoiler:Orion]] BackFromTheDead, but decided against as [[spoiler:his]] death had become a large part of the mythos & they felt it had to stick for the impact it had on the characters.
** If the show had continued, [[spoiler:Jeff & Lester]] would have become Team Bartowski's [[Franchise/JamesBond Q]].
* YouLookFamiliar: The actor who played Yuri the Gobbler had also played one of La Ciudad's goons.