Alice knows that if she ever turned her back on Bob, he might stab her in the back. Surely, Bob is too dangerous to keep around... but, on the other hand, so long as Alice keeps an eye on Bob, she'll always know what he's doing. So, what better way for Alice to keep an eye on Bob than to keep Bob around Alice?
Often times, Alice keeps Bob close by appointing him to a position of power, such as her personal adviser. Alternatively, Alice might associate herself with Bob's friends, or on rare occasions, might even try to form a relationship with Bob himself. Anything that can work to keep Bob under check at all times.
This trope does not necessarily apply only to villains or traitors, but also to any character who could become a dangerous loose cannon if left unmonitored, such as a Blood Knight. It is safer to keep these characters around you, so you always are aware of their actions and motivations, than to risk letting them slip under the radar. In the case of the aforementioned Blood Knight, it is safer to keep the Blood Knight in your army than it is to discharge him and not know where he is or whom his next target might be.
This trope is risky to pull off, since it can backfire and Bob will have a much easier time stabbing Alice in the back than he would have if she stayed far away from him.
- Bleach. Captain Shinji Hirako of the 5th Division distrusted Sosuke Aizen and made Aizen his lieutenant so he could keep an eye on him. Aizen found a way around this by using a dummy. Ironically, Aizen explains that the fact that he never trusted him is how he was able to make it work. If Shinji had gotten to know Aizen better, then he would've noticed that the double's mannerisms didn't quite match his own. Since he kept Aizen at a distance, he never learned enough about him to see through the deception. In the end Aizen used his position to perform evil experiments and eventually turn Hirako and a number of other high level Soul Reapers into hollows.
- In Death Note, L's primary tactic at one point is to actually keep Light handcuffed to him so he can't act as Kira. This backfires on him because it allows Light to come into contact with the Death Note again.
- In Code Geass, Lelouch does this to Rolo during the Geass raid and the second Tokyo battle before he intends to dispose him as payback for murdering Shirley and/or attempting to replace Nunnally (the former doesn't happen in the movie versions, but the latter still remains one reason). Unfortunately for the former, Rolo makes various other Black Knights suspicious by telling them he trusts him the most. Should've reined him in a bit more.
- Earlier in the season, Villetta and Rolo are assigned to the OSI detail to watch over Lelouch in order to keep him from using his Geass or becoming Zero. Lelouch manages to flip the script on them both via blackmail of the former's relationship with Ohgi, and convincing the latter that he has no future with Britannia, respectively. (Unfortunately, he fails to keep an absolute leash on either.)
- Naruto: The 2nd Hokage never trusted the Uchiha clan and felt their extreme emotions meant that even as allies they were a FaceHeel Turn waiting to happen. Later events would prove that he had a point. He put them in charge of Konoha's law enforcement so that he could more easily keep an eye on them.
- In Aruosumente, Oracle Kian's original thought behind taking in Lante and Dante, with the latter being a loose cannon waiting to happen. He reasons it's better to keep them close than to have them fall into enemy hands and be used as weapons. It is also the reason Lante and Dante have been made commanders of the White and Black Knights respectively.
- Doctor Strange: Stephen Strange first asked the Ancient One to teach him magic after learning that the Ancient One's disciple Baron Mordo was plotting to murder his master. Accepting Strange as his new disciple, the Ancient One revealed that he was fully aware of Mordo's actions for some time; "The student can have no secrets from his master." He kept Mordo around so he could keep a close watch on him.
- Apotheosis (MHA): Deconstructed. As Izuku notes, those with powerful and/or destructive Quirks but poor personalities and character like Endeavor and Katsuki Bakugou are allowed — even encouraged — to become heroes because those up top are scared they'll become dangerous villains instead if denied the chance. However, all that is doing is giving them what they want instead actually correcting the problem. For what it's worth, it is a legitimate concern; Izuku only managed to avoid the issue with Endeavor by taking his Quirk. Bakugou, meanwhile, was put on probation with the threat of expulsion to force him to shape up, taking advantage of his unending desire to be a hero and his repressed conscious.
- Michael Corleone of The Godfather Part II is the Trope Namer, who learned this trope as a lesson from Vito and practices it with Roth and Don Altobello. It backfires spectacularly.
- In Blade II, Blade knew that Scud was a traitor the whole time, but kept him around for this reason.
- Implied in the TRON: Legacy bonus feature "The Next Day." Alan Bradley is going over his plans for Encom now that Sam Flynn is (nominally) in charge. Roy expresses concern over Ed Dillinger Jr., the son of their enemy from the first film. Alan shrugs, saying that Junior's "earned his place," but seeing as Junior really is up to no good scheming with a resurrected Master Control, this trope would make sense.
- In The Chronicles of Magravandias, Valraven, the emperor's most valued general, is married to Princess Varencienne for this purpose.
- Robert Heinlein's The Moon Is a Harsh Mistress. When the conspiracy learns the names of all of the Lunar Authority's spies, Wyoming Knott wants them to be killed but Professor Bernardo de la Paz has other plans.
Professor de la Paz: The thing to do with a spy is to let him breathe, encyst him with loyal comrades, and feed him harmless information to please his employers. These creatures will be taken into our organization. Don't be shocked; they will be in very special cells. "Cages" is a better word. But it would be the greatest waste to eliminate them - not only would each spy be replaced with someone new but also killing these traitors would tell the Warden that we have penetrated his secrets.
- Leonard of Quirm in the Discworld books, the Disc's equivalent of Leonardo da Vinci. He's not a villain as such, just unconsciously very dangerous: an amiable old man who is brilliant and naive enough to invent all sorts of misusable devices (implied at one point to include nuclear bombs, which he thinks could be useful in civil engineering "when the mountains get in the way.") Lord Vetinari has him locked in a cell in the palace with a supply of art materials to keep him occupied.'
- There's also the Thieves' Guild, which are an actual civic power in Ankh-Morpork, allowed to legally operate so long as they pay tax and eliminate unlicensed thieves. This method decreases crime in the city while keeping the Guild profits about the same. It also conveniently gives Vetinari a list of the Thieves' names and addresses if the Guild ever fails to uphold their arrangement.
- In The Mysterious Benedict Society, Reynie, Constance, Sticky and Kate are four kids who are sent as secret agents to the mysterious Learning Institute for the Very Enlightened run by the Evil Genius Ledroptha Curtain. Reynie's talent for mastering the material on Mr. Curtain's tests gains Curtain's approval and the two get drawn into a conversation in which Curtain expresses his suspicion of Constance, who often sleeps in classes and is rude and surly to the teachers. He tells him that he doesn't understand her and therefore he doesn't trust her. Reynie replies that this is perfectly understandable, "but you know what they say about those you don't trust." Mr. Curtain replies that no, he doesn't know what it is that they say and Reynie says "If you don't trust them, keep them close." This amuses Mr. Curtain, but also makes sense to him, and it throws suspicion off Reynie, while also serving Reynie's purpose of allowing Constance to stay at the Institute. Later, Mr. Curtain keeps around Martina Crowe on the same principle, even though Sticky tells him that she forced him to help her cheat, and he believes him.
- In A Song of Ice and Fire, Jaime Lannister ponders a different version; keep your friends behind you and your enemies in front (where you can see them).
- In the Warrior Cats book The Darkest Hour, Firestar thinks that Darkstripe will be less of a threat in ThunderClan - where Firestar can keep an eye on him - than he would be if he left to join Tigerstar. This doesn't last long, however: just a few days later, Darkstripe attempts to poison a kit that saw him scheming with Tigerstar's deputy, Blackfoot.
- The goblins in Goblin Quest take a different view: "Keep your enemies close and your friends closer. That way your friends are between you and your enemies". This demonstrates a culture where most members of the tribe would cheerfully double-cross any other member in the name of personal survival.
- Thrawn introduces a caveat to the classic "friends close, enemies closer" phrase: To Thrawn, allies should be kept close (and enemies closer), but true friends don't need to be "kept" anywhere and deserve trust and freedom.
- In Babylon 5, G'Kar alludes to this trope and then says that humans probably stole it from the Narn.
- Garibaldi alters it to include a second sentence: "And if I don't know which one someone is, I get really close." According to one of the EU novels, this was the reason for Sinclair to tell Garibaldi "Stick close to the Vorlon and watch for Shadows. They move when you're not looking." - he was trying to tell his friend that they both moved when people weren't looking and shouldn't be trusted.
- In CSI: NY, Detective Mac Taylor alludes to this trope:
Detective Mac Taylor: You know what they say: keep your friends close and your enemies closer - and if that doesn't work, kill 'em.
- As quoted by Jack Donaghy on 30 Rock.
Jack: The Italians have a saying, Lemon: "Keep your friends close and your enemies closer." And although they've never won a war or mass-produced a decent car, in this area they are correct.
- In the Supernatural episode "Devil May Care", Sam and Dean bring Crowley, the King of Hell, inside their heavily warded secret bunker.
- A slightly modified version spoken by Gaheris Rhade in an Alternate Universe episode of Andromeda regarding Tyr: "Keep your friends close. Keep your enemies under constant surveillance." It helps that there's nowhere on Andromeda that Tyr can go where the Spaceship Girl won't see him.
- Falcone in Gotham knows Mooney wants to usurp his place as the crimelord of Gotham but continues to keep her as his go-to gal and even had a civil conversation with her as his men beat Mooney's lover behind them.
- Game of Thrones. Discussed in "The High Sparrow". King Stannis suggests to Jon Snow that he might want to transfer Alliser Thorne. Jon says that he heard it was best to keep your enemies close, but Stannis retorts that whoever said that didn't have many enemies. Instead Jon promotes Thorne but transfers Janos Slynt, Thorne's closest supporter. Slynt refuses to be transferred and is executed by Jon Snow, firmly establishing his authority when Thorne refuses to oppose the execution. In the long run however this backfires, when Thorne leads the assassination attempt on Jon Snow.
- In Mad Daedalus, King Minos tries to capture the inventor Daedalus to prevent him from escaping into the future and taking his technological wonders with him.
- In LEGO Knights' Kingdom, King Mathias knows that Vladek is a dangerous, brooding, scheming fellow who would usurp the throne if given the chance. So, he appoints Vladek to the position of his personal adviser so he can always keep an eye on Vladek and make sure he's not up to no good. Unfortunately, this backfires, since Vladek doesn't remain content being the king's adviser.
- Discussed and defied in Penny and Aggie when Meg, after humiliating Penny in front of a boy she likes, invites her and her friends to a Slumber Party. Penny accepts, explaining afterward to her friends that Meg is practicing this trope, but that she plans to use it against Meg. At the party, Penny takes embarassing candid photos of her and shares them with her classmates, thereby ending Meg's reign as queen bee.
- This is Roy's reason for keeping Belkar as a member of The Order of the Stick. Roy doesn't trust any prison enough to keep Belkar from breaking out and going on a rampage, whereas so long as Belkar is working for the Order, the other members can keep him in check and direct his sociopathic tendencies towards evils that are more dangerous than him.
- In The Nostalgia Critic's review of The Transformers, Optimus Prime discusses this trope when wondering why Megatron keeps Starscream around despite the latter always trying to betray the former. According to Optimus Prime, Autobots don't believe in this trope and instead Just Shoot Him.
- In Kickassia, this may be the reason why the Channel Awesome team decided to keep "Fritz Von Baugh" around even though they all knew that he was obviously Kevin Baugh in a Paper-Thin Disguise. This ultimately backfires, as it allows Fritz Von Baugh to undermine Kickassia's government.
- In Worm, Coil does this with his employee Tattletale, keeping her close so that she can't get help from other groups, monitoring her purchases and being sure that he knows what she's doing. Unfortunately, it backfires when she takes the opportunity to hire his mercenaries out from under him, since he was nice enough to put her in proximity with his officers.
Tattletale: The problem with keeping your friends close and your enemies closer? It puts your enemies in the midst of your friends, so they can discuss better means of payment with the right team captains.
- Archer: Partly why Malory keeps Dr. Krieger around, because of what he could become.
Malory: And if there is one thing I have learned in all my years as a spymaster, it's that you keep your friends close and possible genetic clones of Adolph Hitler closer.
- In Hot Wheels Battle Force 5, Kalus promoted Grimian to second-in-command because a wise one once advised him about this trope.
- In The Transformers, this is generally understood as one of the major reasons why Starscream is second-in-command to Megatron despite (or rather, due to) his Chronic Backstabbing Disorder.
- In Total Drama, Heather uses her understanding of what reality show producers like best to get to the final three of Island, and so despite hating Leshawna, acts nice to her for this reason. In Action, it's Leshawna using this justification for wanting Heather on her team.
- In the third season of My Little Pony: Friendship Is Magic, episode "Keep Calm and Flutter On" Discord of all people is entrusted to Fluttershy to remain under surveillance and be reformed. Which he apparently does.
- The Simpsons:
- This is how Homer gains his position at the nuclear power plant. He led a protest against the plant's numerous safety violations, so Mr. Burns placated the protesters by making Homer the head of safety. Burns explained to Smithers afterwards that this allows them to keep a close eye on Homer and punish him in due time. (However, this seems to have completely failed—in subsequent episodes it becomes a running gag that Burns never remembers who Homer is, in spite of how often they interact.)
- In "Burns Verkaufen der Kraftwerk", Mr. Burns sells the nuclear power plant to a pair of Germans for $100 million and those new bosses, being a bit more grounded in reality, have the sense to fire Homer. Burns attends Moe's Tavern in jubilence only to find a drunken Homer berate him. This was profound enough for Burns to decide that he lost the "respect" (read:fear) of the townspeople, and he immediately bought it back, and hired Homer again citing this trope by name, like the example above, schemes to make Homer's life miserable/punish him but the whole thing only seemed to enforce Status Quo Is God.
- Fit Tony deconstructs this in "Donnie Fatso" by stating his enemies could easily strike him if he kept them close.