Rozalin: ...Y-you... You are really going to trust me? I am the daughter of Overlord Zenon. I am a demon, and you intend to kill my father. What part of that equation gives you the notion that you can trust me!? Are you mocking me? Adell: No, no. I'm not. It's just that... I promised myself that I would trust you. And you know how I am with promises...
Simon too, later on. Part of the symbolism is that the entire brigade supports him and backs him up, and in turn relies on him to win the day. Just as a drill takes most of its power out of it's weight and the force behind it, but still relies on the tip to actually pierce the target.
Kanokon provides our protagonists with an All Your Colors Combined sort of super mode that requires an open heart to work. In other words, trust. We learn this after that trust is lost, naturally.
In Fullmetal Alchemist, though Ed rarely holds back in showing how much he hates Mustang, he seems to trust him almost implicitly, due to the fact that Mustang's been keeping his and Al's secret for four years. He evens comments in one episode of Brotherhood:
Ed: The colonel might be a bastard, but he's trustworthy.
Baccano! has this involving the immortal 10 year old, Czeslaw Meyer. No, he's not the sweet kid who makes the huge cast of assortedcriminals find themselves. After a couple hundred years of bad experiences, he has issues trusting anything in this world. The anime and novels has Issac, Mirria, Ennis, Maiza and Elmer to drive the point to him. It only takes about 70 years.
In Scrapped Princess, Shannon has trouble tapping into his hidden D-Knight abilities because he doesn't trust Zefiris enough to use them. When they first try combining, his power gives out after several minutes of fighting.
In the Violinist of Hameln the 'Trust' between Hamel and Flute is exactly what stops him from turning completely into a Mazoku. Also, Trust is what gives Flute the power to stand up and hold Mazoku!Hamel's hand, smiling- after being stabbed by him.
In Naruto, the title character was shunned from birth by everyone in the village with the exception of Iruka-sensei. If Naruto didn't have Iruka's trust, things may have been a lot worse. (just look at what happened to Gaara)
Also Chouji. Constantly teased for his weight, but reveals during a major fight that if you insult Shikamaru (the one who actually believed in him), he will kick your ass.
In Full Metal Panic!, pretty much all the moments where Sousuke starts falling for Kaname is when she tells him she trusts him completely. No, he doesn'treactvery well romantically when she tries to seduce him in skimpy outfits, but boy does his heart start beating fast when she appeals to his trust issues. Justified in that it's shown that all his life, he was never really able to trust anyone like that... so it definitely moves him when she's able to believe and trust in him like that.
To go further on Sousuke's trust issues, it's pretty much said outright that his lack of the Power of Trust is the main reason why he has problems using the Arbalest's Lambda Driver. Because he passively hates the machine and is unwilling to trust it, it can't always function right.
Hiei of YuYu Hakusho sheds his initial tendencies toward world-conquering and the accumulation of zombie mind slaves for no apparent reason other than 'dumbass got lucky and now I'm on parole,' but his Heel-Face Turn is confirmed at the 'Gate of Betrayal' in their first team story when Yusuke, with manly beaming smile of trust, nominates him to dart over and pull the lever to save them all, while the rest of them split his load of the crushing weight, and after some debate he actually does it.
Somewhat ridiculous in that Yusuke asked him because he was fastest, and if we factor in his hesitation time actually anybody else would have been faster. That he was shortest and therefore couldn't actually be helping them hold it up anyway would have made more sense, but been a lot less cool.
He was probably the only one fast enough not to get killed by the huge rock they drop on you in punishment for keeping faith with your comrades, so that worked out okay.
What may be odder is the Heel-Face Turn-inducing trusting smile coming from a cynical fourteen-year-old who has never had any friends ever except this one girl he played with as a little kid because he's a jerk and bad with people and doesn't like people anyway. Dying is good for the soul.
Hiei's initial psychosis was probably the magic sword messing with his head, anyway.
A big part of the meister/weapon teams in Soul Eater. More so than strength, arguably more than courage, it's mutual trust that counts; its indicated that without it the teams could not function. e.g. Black Star and Tsubaki working out how to use the demon blade mode, Maka and Soul when fighting the Clown and later Giriko.
Trust between partners is also a major theme in Tiger & Bunny. Throughout the entire series, the eponymous characters, forced to become partners in episode 2, must learn to trust each other, both personally and professionally. Indeed, explicit and implicit lack of trust for each other causes the most rifts in their friendship; conversely, expressed trust in the other helps them grow as people and partners.
In the first arc of Higurashi no Naku Koro ni, this is invoked by Rena who tries to bring Keiichi back to reality (note: he was high on Hate Plague at the time), after murdering Mion in front of her - she even pairs this with an attempted Cool Down Hug and the words "Please, trust me..." - but it is ultimately subverted when Keiichi smashes her face in with his metal bat.
However, this is only remembered by Keiichi in the appropriately named "Atonement Arc". He proceeds to help Rena overcome her bout of Hate Plagueagain (he and the rest of the gang attempted to help Rena earlier in the arc, grilling her on why she didn't reach out to them before resorting to murder). Thistime, itworks.
Trust in his teammates (instead of viewing them as a collection of physical attributes to be exploited at gunpoint) is part of Hiruma's Character Development in Eyeshield 21.
In the Christmas Bowl, Sena realizes that Hiruma was trusting in him to get past Yamato, the real Eyeshield 21, past the point where it would still be statistically possible for their team to win. It spurs Sena on to do just that.
In the same game, Hiruma throws a blind pass as he's being sacked, even though holding onto the ball would have been the safer option. Based on the opposition's defensive formation, he just knows that Yukimitsu will be exactly where he needs to be to receive that pass. Touchdown.
The Power of Trust is intertwined with The Power of Friendship in Berserk. Guts is very wary of people because his adoptive father, whom he admired above all else, sold him out to a pedophile and was raped as a result. Over time, he's repetitively put in predicaments that require him, a loner by nature, to place his trust in the hands of other people. Sometimes, the outcome is fruitful, but other times not so much...
Attack on TitanDeconstructs this - Yes, you should trust you teammates and can rely on them from time to time, but outright doing so only and not relying on your own strengths is suicidal for both sides
Inverted in Mighty Avengers. Evil god Chthon, who gets more powerful the more people believe in his existence (which he enforces via terror), finds out that there's even stronger source of power for him - the lack of trust for a man who was trying to stop him, Henry Pym.
The Return - Want to get a group of succubae working for your mercenary army? Col. Edwards finds this method works nicely.
A major theme with Pony POV Series. Twilight even points out that trust is instrumental for friendship to exist. In fact, it originally was an Element of Harmony until Discord destroyed it, but Twilight points out that trust is still a requirement for the Elements, as without it, The Power of Friendship can't exist to power them. Celestia actively applauds her for figuring this out.
In Duel Nature, Twilight tells Bronze Bell that she has faith that he can decipher the location of the local Temple of Doom even if he doesn't believe he can, which inspires him to go ahead and do it. He gives them a fake location, but they find it anyway.
The thirteenth story of the Facing The Future Series, Ancient History has this big time. First, Tucker proves he trusts Tanya enough with her memories of the ordeal while he wiped it from the rest of the city, and Danny and Sam do this as well when they trust Tucker enough to leave the Scrab Scepter in his hands.
Horribly subverted in Reservoir Dogs. Mr Orangefeels obligated to confess to Mr White, who has taken the bullet for him, that he was the rat all along. The latter then tearfully, but promptly, executes him.
Sean:Trust: is a very important thing. *Tosses apple to student who's slouching in his seat* Jeremy- you want to tell us why this is?
Student: Because trust... trust is... life.
Sean: Mm, well, that's- very deep, thank you, Jeremy.
In Aladdin, just before leaping out of the window of a high building, Aladdin offers Jasmine his hand and asks: "Do you trust me?" Later he asks the same thing when inviting her for a carpet ride, which gives away his disguise.
Jasmine's answer both times is: "yes", the first time uncertainly, the second time with a smile.
Her initial response, a surprised "what?", is also the same both times, the first time more panicked while the second is more confused before she figures it out and smiles knowingly.
In National Treasure, Ben has to save both Abigail and the Declaration of Independence. He asks if she trusts him; she says yes. He promptly drops her in order to save the priceless document. He apologizes afterwards, but she simply assures him she would have done exactly the same thing.
In Moulin Rouge!, the lack of this is the main difficulty in seeking true love with a prostitute: "When love is for sale to the highest bidder, there can be no trust. Without trust, there can be no love!"
In Tangled, Rapunzel assures Flynn that Fate or Destiny brought him to her — Flynn assures her it was a horse — and so she will trust him — a horrible decision, he assures her — and yet it pans out well. Flynn's enough of a Gentleman Thief that his attempts to get her to rescind the deal do not actually endanger her, and after a while and some adventures, he goes out of his way to help her.
In High Deryni, Bishop Arilan reveals his Deryni powers to the human Bishop Cardiel in an effort to strengthen their partnership, and he explicitly asks Cardiel to trust him regarding his arcane secrets and the commitments they entail. (Arilan is not only the first ordained Deryni in Gwynedd in two centuries, he is also a member of the secretive Camberian Council.) Arilan shares what he can with Cardiel so they can both lead their side of the schism against Archbishop Loris (which is over Deryni in general and certain ones in particular). Together, they help reconcile the Church with King Kelson before the coming Torenthi invasion.
In King Kelson's Bride, Liam and Mátyás escort Kelson, Morgan and Dhugal to visit the Nikolaseum, a great memorial tomb for a Torenthi prince who saved the life of his king in battle against the forces of Gwynedd a century earlier. There, Liam and Mátyás ask for Kelson's help to foil a plot against Liam. In deciding what to do, Kelson says, "Someone must trust, if we are ever to end what brought Nikola to his death." In a mental conference with Morgan and Dhugal, Kelson asks if he should trust them, and Morgan replies, "As you say, my prince, someone must trust." Mátyás offers the location and pattern of a Transfer Portal nearby, and Kelson and Morgan allow Liam to bring them to one of Mátyás' private chapels via Portal (with Liam in control, since he knows their destination) to confer in detail. This reciprocal exchange of trust sets them on a course towards a deep friendship forged in adversity.
Later in the same book, Létald, the Hort of Orsal says in a meeting with Liam and Kelson and their advisers, "It seems we must all trust one another far more than we had planned or dreamed." The meeting is to discuss measures to take against the escaped traitor Teymuraz.
In Sandy Mitchell's Ciaphas Cain novel Death or Glory, Cain catches their guide Sandy Kolfax drinking. Cain demands he hand over the booze; then he hands it back and tells Kolfax to bring it to their medical man for use as supplies, to undermine his resentment.
In Graham McNeill's Warhammer 40,000Ultramarines novel The Killing Ground, Uriel is subjected to three ordeals to prove that he is untainted by Chaos. The second involves pulling a sacred relic from boiling oil. When he says before that he will succeed, Leodegarius, administering it, says he hopes he will, with obvious sincerity; when he is struggling with the pain, Leodegarius looks at him with obvious desire to have the evidence to prove his innocence. This confidence is what gives him the strength to do it.
In Snow Crash, Uncle Enzo takes some enemy agents prisoner. He spares their lives in return for their service. He then deliberately leaves them unguarded, knowing that the trust he's showing them will be more binding than anything material. He's right... not that it matters in the end.
LaraNotsil of the X-Wing Series, sitting in her new X-wing in flight on her first mission with Wraith Squadron, sees that Wedge Antilles, Ace Pilot and hero of the Rebellion, is flying ahead of her, no shields. For years she'd been going out in false identities and betraying her comrades at the behest of her handlers, but now her handlers were dead, and she discovered that she could not stand treachery. Her resulting train of thought is what first triggers her Loss of Identity, Double Consciousness, and attempts at Becoming the Mask.
Such an odd feeling. Wedge Antilles was under her guns, yet he trusted her with his life.
He had no reason not to, of course. But he did. No one had in-how long? Forever.
She could eliminate him with a twitch of her finger.
It should have been tempting. Yet, somehow, it wasn't.
Such an attack would be treacherous.
In Simon Spurrier's Warhammer 40,000Night Lords novel Lord of the Night, Sahaal reverses the process: when he confides even a fraction of the truth to a woman he is deceiving, it feels good. At the climax, he trusts her — and finds she was murdered and replaced by a shapeshifter. Later, when he is trapped in his mind by an Eldar, he is met by a psyker who is in a situation similar to his own and they end up running away together from everything.
In the Harry Potter books it is a major plot point whether Dumbledore's trust of Snape is correct or if he is a Horrible Judge of Character. Dumbledore many times asks Harry to trust him. Let's just say there is a lot of trusting going on, much of it rather reluctantly.
Dumbledore wants to trust everyone. Half the time it works, too. To the point that the only person Dumbledore never fully trusted was Tom Riddle aka Voldemort.
Very few of the heroic characters actually like Snape, but they repeatedly tell Harry that Dumbledore trusts Snape, and since they trust Dumbledore they must also therefore trust Snape as well.
In John C. Wright's Orphans of Chaos, Amelia recounts a fantastic story and all the other children immediately vote that they are in a crisis and must take all precautions. She is moved by their trust.
If you doubt and hesitate, we are lost! Why should I bring you up out of the pits to betray you now?
In "The Shadow Kingdom", Kull is given a stolen gem to inspire trust, because he can now betray the man.
This is one of the central themes of Worlds of Deep Space 9: Cardassia in the Star Trek: Deep Space Nine Relaunch. Vedek Yevir appeals to the virtue of trust in order to prevent a 14-year-old would-be suicide bomber from going through with the attack.
In L. Jagi Lamplighter's Prospero Regained, Astreus mocks Miranda for declaring she would never trust him, telling her to trust no one and they could write on her tombstone "She trusted no one."
The premise of Nevil Shute's Trustee From The Toolroom is the trust placed in Keith Stewart by his sister and her husband to look after their daughter. While they never doubted that he would act honourably, until the situation demanded that he rise to the occasion neither they nor he guessed how capable he would be. Also, Stewart’s articles for Miniature Mechanic magazine serve as a passport of trust for him to gain the help of a worldwide community of model engineering hobbyists.
Live Action TV
In Smallville, so, so many times, and tons of it between Clark and Chloe. It showed a fracture between their friendship - the strongest and most enduring in the whole show, when Clark thinks he can't trust Chloe in Collateral. Lois calls him out of it and says he knows in his heart that he could. He is just too scared and hurt.
Doctor Who: almost every Doctor, at one point, said, "Trust me, I'm the Doctor," or variations.
This goes both ways with his companions, and can make for some Crowning Moments of Heartwarming. The "I believe in her" speech from The Satan Pit is a great example of this.
In an episode of Doctors a terminally ill woman and her son successfully use this on the woman's homeless brother to persuade him to look after the boy when she dies.
The Power of Trust is a major theme of The Sarah Connor Chronicles, where John Connor absolutely trusts Cameron to protect him, even after she goes haywire following damage to her chip and tries to kill him, and then suffers temporary amnesia.
Subverted with Cameron's view of Sarah. She doesn't trust Sarah to do what needs to be done to protect John because, while Cameron has pure Orange And Blue Morality, Sarah tries to spare the lives of those she thinks may be innocent. This comes back to bite them when Sarah lets a teenage thief go after promising Cameron she'd kill him, and the thief later tells Cromartie where the Connors live.
Firefly: River's trust actually managed to make Simon a Determinator . For some time he was the last person left that she could trust. And the knowledge of that fact probably pushed him on.
Mal also discusses this at the end of "Our Mrs. Reynolds," when he catches up to Saffron.
"Now you got all this education, and made me look the fool without tryin', but I still got a gun to your head. That's 'cause I got people. People that trust one another, that do for each other and ain't always lookin' for the advantage."
And at the end of "Trash" (another episode involving Saffron, actually) Simon has learned of Jayne's attempt to turn him and River over to the Feds in "Ariel", and has an injured Jayne at his mercy on the operating table:
This theme almost becomes Hatter's Arc Words on Alice. On first meeting her: "I see. You don't trust me." Midway through the mini-series: "You still don't trust me?" On saving her life multiple times, getting tortured, beaten, and pretty much going through hell in the attempt to Make His Beloved Happy: "You trust me now?" Alice: "Completely."
But to be fair to Alice, he certainly doesn't look or behave like a particularly trustworthy guy.
Kamen Rider Blade: All of Hajime's transformations come from being trusted. Really, all of them.
Kamen Rider Double takes this in an unusual direction: back Detective Jinno was apparently extremely easy to fool (even falling for the old Look Behind You bit), but was so kind and earnest that it made the people who lied to him want to become better people so those lies became the truth. The flashbacks revealing this imply that this is what turned protagonist Shotaro Hidari from a juvenile delinquent into an honest man.
The X-Files: Mulder and Scully trust each other so closely and so intensely that if someone tells one of them something and the other contradicts it, they will pretty much believe the other without even thinking about it. Essentially, The X-Files is Power of Trust turned Up to Eleven. The show's tagline is "Trust no one"—and they don't. Except each other, no matter what.
Not always, though, which since this trope is Up to Eleven, causes so much more hurt and confusion than it usually would. A big plot point in season six and part of season seven was Mulder trusting his ex-partner/ex-girlfriend Diana Fowley over Scully. Scully and the Lone Gunmen even had hard proof that she was working for the Big Bad, and Mulder refused to believe it. It almost caused the break-up of the partnership. Of course, that was what Diana Fowley had wanted all along.
Or the episode "Wetwired", where Scully is affected by subliminal messages on TV that Mulder betrayed her to the Cigarette-Smoking Man (Mulder himself is not affected "thanks" to his red-green color blindness). Seeing the trust they've built up to that point just go poof is extremely disturbing, almost traumatizing. Especially for Scully, once she snaps out of it.
The brothers' trust in each other, or occasional lack thereof, is a big part of the series. It's brought up repeatedly that to hunt together and live as they do, they need to be able to trust and rely on each other completely, so they both take it very hard when they catch the other brother in a lie or keeping secrets, no matter how big or small. On occasions where Dean's faith in Sam/Sam's love for him has been shaken, Dean generally gets pretty destructive, such as in the above instance where he was ready to say "yes" to Michael and kick-start the Apocalypse, partially because he worried Sam would eventually cave into Lucifer. Sam seems to have always trusted Dean unquestioningly, but that was finally broken this year when Dean tricked Sam into accepting an angel possession to save his life (saying outright that he knew Sam would rather die) which has had far-reaching consequences for their relationship and on the show.
The slow, hard-earned building of trust between Inspector Lynley and his partner Barbara Havers is what makes watching The Inspector Lynley Mysteries worthwhile. Nathaniel Parker and Sharon Small sell the hell out of two absolutely broken people coming together against all odds and, through fire and flames, arguments and alcohol, learning to trust each other with no conditions, no questions, and no regrets. From that trust comes Character Development ahoy - Lynley becomes less snobbish, patronizing, and elitist and finally has one person who can look his dark side full in the face without flinching and make it lighter, and Barbara softens, opens, and blossoms and finally has one person who accepts her and loves her exactly as she is, fiery temper, deep insecurities, and all. Through it all they become one of the tightest-knit partnerships in the history of fictional law enforcement - oh, and sometimes they solve murders, too.
This is a huge theme of Merlin, particularly in regards to Prince Arthur's Character Arc. Essentially, every single person in his life has betrayed his trust at one point or another. His faithful servant Merlin is hiding the fact that he's a powerful sorcerer. His father lied about the circumstances of his mother's death. His half-sister betrayed him and tried to take over the kingdom. The court physician knows all the secrets of his life and reveals none of them. His uncle is plotting against him. His best knight is controlled by dark forces in order to seduce his future wife. Ironically, the one person that Arthur can trust is the character who is best known for her infamous betrayal: Guinevere. In this version she is caught kissing Lancelot on the night before her wedding to Arthur, but was under an enchantment at the time and had no intention of being anything but 100% faithful to Arthur.
Mrs O'Brian's childlike trust keep O'Brian and Kira chaste in Star Trek: Deep Space Nine "Looking for Parmach in All the Wrong Places". In the end it is too much of a Kick the Dog for them to be able to betray it. The whole thing is mostly Played for Laughs (due to how uncomfortable the two of them are around each other) in the B-Plot of the episode.
Several Game Shows have used the Prisoner's Dilemma as part of their final rounds; particularly Friend or Foe, Golden Balls, and Take It All. In all of these cases, a shared pot is at stake; the two contestants either elect to split the prizes, or take them all, deciding in secret.
Subverted in Sledge Hammer!, where a sure guarantee of things going horribly, horribly, wrong is Lieutenant Hammer assuring anyone standing nearby to
Hammer: Trust me. I know what I'm doing.
The aptly titled "A Matter of Trust" is all about how trust is pretty much the most important part of a relationship.
Averted in a way sure to get at least some players to curl up in a ball of guilt in Knights of the Old Republic, where when playing Dark Side, Mission is the last person to believe in you, and risks her life on the hope that there's enough good in you left not to kill her. Besides proving her wrong, you can add the twist of making her trusted friend Zalbar kill her, much to her despair and disbelief.
Also comes into play during the fight with Sith Bastila on the Star Forge. You can choose to give her up as irredeemably lost and kill her, but most of the "good" conversation options involve bringing her back to the Light Side by saying you believe in her/the love between the two of you. At the end, she asks how you can trust her so completely. The player can choose to change their minds and decide "I guess I can't" and really break her spirit, or say they trust her enough to leave themselves open to her attack. This is what finally snaps her out of her torture-induced fall to the Dark Side.
Also is the basis of Carth's entire character arc. He spends a lot of time railing about how he does not trust the Jedi, Bastila, or you... all with damn good reason, it turns out. At the end, he has enough trust in you to forgive you for your crimes as Revan. Playing female? You can validate his trust (Light Side or the Take a Third Option that was cut from the game) or damn you both.
In Mass Effect 2, it's only the trust between Shepard and The Squad members that gets them all through the Suicide Mission in one piece. Fail to gain their trust and you'll be looking at a long row of caskets.
In a more subtle example, trusting all your (permanent) squadmates unconditionally will usually bring about the best results in the long run. Also, as long as you show full trust and support towards them, none of them will betray you, not even the shadiest ones (well, except Morinth but to recruit her, you must have already betrayed another teammate's trust), and will unconditionally support you in return.
Trust is one of the "Spirit Commands" in Super Robot Wars, and partially recovers the HP of another unit. Or your own unit; believing in oneself is powerful too.
Note the stronger version is called in Japan "Friendship".
Touched upon in The World Ends with You. Neku is told repeatedly to trust his partner, and after the incident where he had to learn that lesson in the first place he does — even when finding out that one of them was using him and out to destroy Shibuya. It is implied that that trust may have caused Joshua's change of heart at the end.The ending's a little unclear on the details.
Ultimately subverted in Squall's case, however, as his problems wasn't that he didn't trust his friends, but that he did trust them...to look after themselves. His doubt was fueled by his enemy, and he had to re-affirm that trust at the end of his independent story.
Played straight but twisted in Valkyrie Profile: Covenant of the Plume. The plume can supercharge any member of your party into a walking engine of death, at the cost of their life following the battle. And it explicitly only works on permanent party members, who have come to trust Wylfred.
Phoenix Wright and Miles Edgeworth of Ace Attorney, in pretty much everything from midway through their second case together and beyond. Which is a very interesting display of trust, considering the fact that since Phoenix is a defense attorney and Miles is a prosecutor, one of them will have to lose whenever they're in court together.
Not at all. Phoenix's first priority is that the innocent are unharmed and absolved of guilt. Edgeworth's first priority is that the guilty are punished. These priorities are the farthest from mutually exclusive one can get, and as long as the truth comes out, both priorities are fulfilled and they both win in the way that truly counts.
In fact, in case 2-4 they Take a Third Option. Edgeworth wins by getting Engarde convicted. Phoenix wins by getting Maya back safely and getting the real killer to admit his guilt. Without Edgeworth trusting Phoenix neither would have happened.
"Zelos...I trust you." Lloyd saying this makes the difference between Zelos being a Fake Defector who helps the party escape the Tower of Salvation's death traps and obtains the final item they need for the Eternal Ring, or truly defecting in the hopes of dying and escaping his destiny.
''...Okay. I trust you. No...I should say...trust me, Guy.'' I guess the Tales Seriesloves this trope. In this case, it's what keeps Luke and Guy together throughout the game, despite the fact that their pasts severely complicate their friendship. Guy trusts Luke enough to return to him, even after the rest of the party abandons Luke for destroying Akzeriuth, and it's reciprocated enough that Luke later allows Guy to stay with the party, despite the fact that Guy's original intention was to kill him.
Though it isn't quite as obvious as the examples above, Tales of Vesperia makes use of this too. One of the best examples is when Flynn is briefly held prisoner in Dahngrest due to a misunderstanding. Yuri breaks in to take Flynn's place, and Flynn points out that if he doesn't clear his name in time, Yuri will have to die for him. Yuri doesn't even blink, just sits down in the cell to wait. Although Yuri's let out early by a third party, Flynn does get back in time. Later, when Yuri basically says he's not afraid of anything because Flynn's watching out for him, it seems perfectly justified.
In Baldur's Gate2Throne of Baal, the reborn Sarevok can be redeemed if you trust him enough. Refusing to use a geas to compel his loyalty is the first step on his long road from Chaotic Evil to Chaotic Good.
Parodied in Portal 2 in which one of the advertisements shows that humans "cannot be trusted" to do cooperative tests with one another. Robots, on the other hand, can trust one another... for about 6 seconds longer than humans.
Essential to the relationship of a reyvateil and her partner in Ar tonelico: "diving" into a reyvateil's mental landscape is one big trust exercise in revealing her secrets to her partner, but also lets her craft and use more powerful song magic. Abusing a reyvateil's trust is a sure way to break and diminish her abilities. In the first game Misha invokes the trope directly whenever Lyner protects her from an enemy attack: "I trust you!"
In Persona 4, Naoto Shirogane's belief in this trope is exemplified by her decision to get herself attacked by the killer: She is completely willing to trust the Investigation Team to save her, even though her belief that they have the power to do so at all is only a guess. Subverted when the Investigation Team utterly blasts her for this, pointing out that if they had failed, she would be dead.
Fire Emblem: Path of Radiance and Radiant Dawn have their support conversations, which allow for power-ups when near the other character supporting you. Can be used for a Back-to-Back Badasses moment if done right. Also, subverted in Tibarn's conversation with Naesala, where the former states that he trusts the latter because they both have the same goal. What does Naesala do? Acts as an informant and gets Begnion to burn Phoenicis, Tibarn's kingdom. It is later revealed that he is under the effect of a blood pact that would kill his people if he didn't follow the demands of the Begnion Senate, so it's at least a slightly averted subversion.
In Juniper's Knot, the boy invokes this when planting the olive tree in the circle, because even if he doesn't trust the fiend to exchange lives with the tree instead of him, checking would ruin her chances of being trustworthy.
Any video game that enforces teams or co-op will have this trope in full force. Only by developing trust within your team can the team achieve victory. If there's no trust, everyone will fall apart.
Basically, the underlying motivation and theme when choosing Forte's Route in GalaxyAngel.
Forte: "Don't worry, I'll watch your back. Can I trust you to watch mine?"
Lampshaded on page 300 "yeah, yeah. And the martians say that "trust me" rhymes with "I love you""
The book The Seventy Maxims of Maximally Effective Mercenaries in Schlock Mercenary notably disbelieves in it, saying for rule 30: "A little trust goes a long way. The less you use, the further you'll go."
In Buck Godot: Zap Gun for Hire, Buck trusting the Beemahs to hold up their end of a bargain after fulfilling his part causes them to go a little further and ensure that humanity will be saved regardless of whether the whole plan works. This impresses even the notoriously antisocial Klegdixal.
Whateley Universe example: Used by Chaka in "Reflections in an Evil Eye" on supervillainess Sahar. And it works.
In Worm, Taylor and Rachel eventually develop this level of trust, to the point that when Taylor is steadily going insane and mind-controlling everyone around her, Rachel willingly steps into her control because she trusts that Taylor will get it right.
Justice League Unlimited: When we catch up with Shayera "Hawkgirl" Hol, she's in a depressed, self-loathing funk because she betrayed the League's trust and made herself a pariah on two worlds. What snaps her out of it is Superman and Green Lantern's announcement that she's welcome to rejoin the League any time she wants.
Superman:I believe in second chances. I believe in redemption. But most of all, I believe in my friends.
Made more heartwarming by The Reveal that she has never been expelled from the League. (Superman, Flash and, presumably, J'onn the Psychic chose to trust her, while only Wonder Woman and Batman voted for expulsion; Green Lantern abstained).
Became a Chekhov's Gun later when Six, his memories of the last six years gone because of the machine, attack Rex and was about to kill him. He stopped because Rex didn't even flinch when he brought the sword down.
Six Not even a flinch. You really believe in me that much kid?
Wolverine and the X-Men: A single moment of trust saved the world and the lack of trust damned it the first time around. Emma betrayed the team, which led to Phoenix running around under the control of the Inner Circle (who just expelled Emma, who wanted to destroy it). She was left tied to a wall when Logan found her. In the first timeline, he left her there. Which meant no one could contain and destroy Phoenix, and thus Phoenix burned the world. A message fragment from Xavier passed back through time was enough to help Logan trust her and free her, allowing her to sacrifice herself for the world.
Teen Titans provides some negative examples. When Robin tries to get Slade's trust as Red X so they can meet, he is Out-Gambitted. Slade notes, "Trust is easy to destroy, but it takes time to build." Terra happily exclaims the Titans trust her. That doesn't end well. In an episode titled "Trust", Robin ends up giving a communicator to "Hotspot". That was actually a Nice Job Breaking It, Hero moment, since it was really Madame Rogue.
In philosophy, the Iterated Prisoner's Dilemma dictates that in the long run, it's better to trust your fellow human beings than try to screw them to get yourself out of trouble. The criminals code against snitching works on this premise, don't snitch today, tomorrow it might be you who they're asking about. The original Prisoner's Dilemma arrives at a different conclusion...
Note also that the "better-to-trust" approach for Iterated Prisoner's Dilemma does not work if there is a known last round of the game - both sides will find it advantageous to screw the other on the last round, which means they will screw each other on the next-to-last round, which means they will screw each other on the third-to-last round, lather rinse repeat.
Newly conquered people should be left their weapons They will, after all, need to defend themselves, and while disarming them will slow rebellion, it will not stop it since they will be able to get arms somehow, and the good will generated by this trust is better against rebellion than the delay. Who thinks so? Why Niccolň Machiavelli. In The Prince, no less.
Older Than Feudalism. Confucius's Analects notes that a state (or society) needs three things to function: an army (coercive force), food (wealth), and trust of its people. If all three can't be maintained, force, then wealth, may be sacrificed. Without trust, no state can survive regardless of how much force or wealth it can muster.
In Systems of Survival Jane Jacobs observes that one of the greatest imperatives for a healthy civilization is for traders (people with "productive" occupations such as farmers, merchants, artisans, etc) to instinctively trust the honesty of others and "guardians" (people with protective occupations such as soldiers, police, firemen, etc.) to instinctively trust each other's loyalty. When you think about it, it is amazing how no one asks waiters whether the coffee they buy is poisoned, and it is possible to buy and sell Amazon without seeing the other party; and how, at least in a few countries, it is possible to hold an election without the losing party being mass-purged to prevent the need for another election and without a military coup being a serious possibility.
Founder of the Boy Scout movement Robert Baden Powell served in the British Army during the colonial era, and noticed a custom among some African warriors of shaking hands with the left, not the right. This was because they held their iconic hide shield in their left hand and their spear in the right- by shaking with the left you put down your defence and left the other guy holding his weapon. It was a huge sign of trust- "I'm not going to stab you, and I trust you not to stab me". Powell liked it so much he adopted it for the Scouts, and, in the UK, Boy Scouts and Scoutmasters still shake each other's hand with the left to this day.
Of course, shaking hands with your right hand shows that your weapon hand is empty (assuming you aren't lying about which hand you use, anyways), indicating that you can be trusted (discounting the chance that you or the other guy will just use the left hand to put a knife in the back once you have the other guy up close). The military tradition of saluting similarly derives from knights using their weapon hands to raise their faceplate, showing that they are unarmed, and exposing their face so they can be recognized by a friend.
This is the only reason that BDSM can be worked into a healthy relationship. If you can't trust your partner unconditionally then the entire partnership is broken for all involved, and someone will end up getting hurt.
One particularly easy way of manipulating people is to invoke this, by calmly putting yourself at their mercy, or acknowledging that it is already so; once this is done, simply state with utmost certainty that you know they are not the sort of person to harm you, no matter what crimes you or they have committed. Once this has been said, only a sociopath or a fanatic will harm you, as the blow to their sense of self and self-pride is too great.