The tendency of fictional works to assume that characters can talk to, share a room with, or travel with complete strangers without doing a background check or even a [[FailedASpotCheck basic spot check]] - and despite this, nothing bad will ''ever'' happen.
In stories where this trope applies, it's usually a near unheard of and an unspeakable crime to actually lull someone into a sense of security and rob them blind. Doing so in such a story is sure to send the character straight over the MoralEventHorizon. Why else would it be pounded into most of the children of RealLife that talking to complete strangers is usually ''bad''?
A JustifiedTrope, as in ancient Greece, [[SacredHospitality accepting aid from and giving aid to complete strangers was shown to be a virtuous characteristic]]. Even in relatively recent times and stories it was not improbable for these sorts of events to occur; strife at them is likely to be due to ValuesDissonance.
When this trope is in play, WalkingTheEarth may become easier.
See also ViolationOfCommonSense.
[[folder: Anime and Manga ]]
* In an episode of ''Manga/CardcaptorSakura'', a strange old man befriends ten-year-old Sakura. [[spoiler:It turns out to be her great grandfather, but she didn't know it at the time and went off with what could very well have been a creep showing unnatural interest in her]]. MoralGuardians were ''so'' very unamused.
[[folder: Literature ]]
* In ''Literature/MobyDick'', Ishmael isn't put off by having to share a bed with a complete stranger, until he discovers the stranger in question is a WildSamoan. Note that that ''was'' how inns and guest houses worked back then. A bed to yourself was very, very expensive. It only gets ''truly'' [[HomoeroticSubtext homoerotic]] when they start spooning and Queequeg insists on grasping his harpoon all night.
* Ayla and Jondolar from the ''Literature/EarthsChildren'' series are constantly meeting new people, who are (almost) always helpful and friendly.
* In ''LonelyWerewolfGirl'' Moonglow and Daniel take in werewolf Kalix no questions asked, even when they know she is a werewolf with self destructive tendencies, no social skills, and hunted by, well pretty much everyone.
* In ''Literature/GalaxyOfFear'', Force-Sensitive Tash Arranda gets feelings around some people. Some of the people she meets, she just feels like she can trust, though sometimes she has to struggle with whether she should or not. Most of these people are the [[HeroOfAnotherStory Heroes of Other Stories]], like the Heroes of Yavin, Wedge Antilles, Lando Calrissian et cetera. It gets to the point where her companions just sort of shrug and assume anyone she likes will be helpful and valorous. However, she can't always sense if someone ''isn't'' trustworthy, so if they are a BitchInSheepsClothing she will [[HorribleJudgeOfCharacter assume the best]], which her companions ''also'' fall afoul of.
* Explicitly averted with ''Literature/TheWheelOfTime''. The merits and shortfalls of playing one's hand close to the chest are closely examined, but there are a lot of bad people in their world.
[[folder: Live Action TV ]]
* Happens all the time in ''Series/HighwayToHeaven''. After meeting Jonathan (the angel) and Mark (his sidekick), people rarely suspect any danger of any kind from these two. In one rare instance (in the episode ''Monster'') where a boy does distrust strangers, the episode is about tolerance of those who are diffent. The boy turns out to be a liar who can't be trusted. Within a day or two of knowing someone Mark and Jonathan will be granted full access to loved ones and personal property beyond what a normal person would trust his own spouse or children to do. In some episodes, Jonathan has convinced near complete strangers to:
** Let him live in their houses.
** Cash in their entire life savings - and hand the cash over to him - to bet on a horse race!
** Take out a mortgage on their homes - and hand it over to him - to invest in the stock market.
** Take his word for it when a loved-one is sick or missing. Most people are satisfied with, "I think I know where to find him," or "You're just going to have to trust me." Never mind that Johnathan is a drifter with no ID and a new job in every episode.
[[folder: Mythology ]]
* Played straight in ''Literature/TheOdyssey'', where ''many'' characters take care of main hero Odysseus.
[[folder: Real Life ]]
* An aspect of this fits into the general aspect of hitchhiking and picking up hitchhikers. Hitchhiking was once considered a perfectly reasonable way for young people to travel, and it was considered bad hospitality to not pick up stranded travelers along the way. Now, the general feeling is to lock one's doors; both the hitchhikers and the drivers expect the other to be scumbags who will take advantage of them, attack them, or [[BreadEggsBreadedEggs take advantage of them and then attack them]].
** This is an example where the trope feeds on itself. As hichhiking has gotten to be less respectable, fewer and fewer "nice" people were willing to pick up hichhikers, which meant that it became even more dangerous and less respectable, feeding the cycle.
** Many an older person will tell you that you didn't have to be as careful a few decades ago as you do now, but it's hard to know if that's the NostalgiaFilter talking if you weren't there.
[[folder: Video Games ]]
* Both ''VideoGame/PokemonMysteryDungeon'' games start in this manner. The first game is particularly jarring, as you, a complete stranger, are tasked to rescue a baby Caterpie.
** Subverted in the second game, where [[spoiler:a Drowzee kidnaps Azurill]].
* In ''VideoGame/TheLegendOfZelda'', many fans have commented on Link's ability to ''just'' walk into anyplace. Few [=NPCs=] will care that much about you breaking pots and taking the goodies inside, or just walking around. Bedrooms aren't off-limits. ''Some'' places can only be entered during the day, though.
[[folder: Western Animation ]]
* ''WesternAnimation/TheSimpsons''' MusicalEpisode "[[Theatre/AStreetcarNamedDesire Oh, Streetcar]]" featured a song which had a message of "You can always depend on the kindness of strangers!" This is a parody of the same line's darkly ironic use in the original play.