Batman: That's the point. Someone like you will keep us honest.
The Morality Chain is a character who is the reason another character is Good. Stereotypically a female love interest, a mother, a daughter, or a little sister; as long as this person is alive, her target of affection will at the very least be a Noble Demon.
There is no Restraining Bolt involved; this person is the only thing preventing someone from happily killing their "friends" and family. (One wonders whether such a form of "goodness" has much value in it until one remembers that it keeps them from killing their friends and family.)
If a Morality Chain were to fall, commit betrayal, or get seriously hurt or die, there is nothing to prevent a FaceHeel Turn happening so fast and so hard that the unchained character is gladly chopping their former teammates into pieces before you can say "Neutral Evil". This is more than the Roaring Rampage of Revenge; everyone has to suffer.
A similar, and often confused with, trope is the Morality Pet. The difference between the two is subtle: A morality pet is a character who redeems a villain. The villain's affection for the pet starts them down the path of good, and even should the pet get hurt the villain will most likely behave as a hero (or anti-hero) in seeking their revenge or protecting the pet. By contrast, the morality chain keeps an otherwise anti-heroic character (such as a Sociopathic Hero) from going full villain. The loss of the chain would spell doom for any involved party, and likely anyone nearby as well. In a nutshell: A morality pet turns a bad guy good; a morality chain stops a good guy from turning bad. That said, the two tropes can certainly overlap: if the character redeems a villain and then also helps keep them from slipping back to evil, they are both a Morality Pet and a Morality Chain.
Sometimes this is Inverted. The death of the Morality Chain motivates the target of affection to become more determined to be good to honor her memory, or something. Usually in these cases the cause of death is either natural, or because of a villain (especially if it's a buddy of theirs that the Morality Chain had disapproved of). Now, if the cause of death is their loved one, either through an accident or because they Kicked the Morality Pet, then they may either go comatose or crazy.
See also: Morality Chain Beyond the Grave, Morality Pet, Cynicism Catalyst, Morality Chip, Living Emotional Crutch, and Driven to Villainy. Contrast: The Kid with the Leash and The Farmer and the Viper.
- Anime & Manga
- Comic Books
- Fan Works
- Films Live-Action
- Live-Action TV
- Video Games
- Western Animation
- In The LEGO Movie, Bad Cop has a morality chain in the form of... himself. While not the dominant personality, Good Cop is strong enough to rein in Bad Cop's sadism and prevents him from using the Kragle on his parents. When Lord Business rubs out Good Cop's face with nail polish remover, Bad Cop goes through with freezing his parents.
- In The Magnus Archives, Basira Hussain serves as this for Daisy Tonner. They're close friends who formerly worked together as Sectioned cops, and Basira is the only reason Daisy hasn't fully given in to the Hunt and started killing ordinary humans as well as monsters. Daisy decides not to kill Jon only because Basira shows up at the last second and intervenes, and when Daisy loses her connection to Basira (for example, during the Unknowing), she embraces the Hunt and turns fully monstrous.
- Mark Briscoe serves as such for his older brother Jay, preventing him from getting in (too) much trouble with ROH censors, from bringing avoidable legal trouble to the company and from causing too much damage on the farm. Mark has plenty of his own vices, such as trespassing, envy and irresponsible handling of farmyard equipment/firearms that Jay is almost completely unable to do anything about.
- Fabi Apache was able to successfully keep her sister Mari on the tecnica path in AAA during the 2010s, though this was preceded by a feud between the two in the 2000s and Mari is liable to fall back into her bad habits when Fabi isn't around.
- In 1st Kings and 2nd Chronicles of The Bible, Jehoiada the priest served as King Joash/Jehoash's Morality Chain as long as he was alive, as the king did what was right in the eyes of the Lord, including having the Temple repaired. However, after Jehoiada died, 2nd Chronicles records that Jehoash forsook the Lord, and served the groves and idols, even going as far as having Zechariah the son of Jehoiada murdered for speaking the Lord's words against the king. In the end, his own servants conspired against him and killed him, and he was not buried alongside the kings of Judah.
- In Survival of the Fittest, Elizabeth Priestly is this to her twin brother Lenny. When she's not around him, he acts even more of a complete bastard to get her back/find her.
- And now that she's permanently out of the picture, we can probably expect even nastier things to happen to anybody Lenny meets...especially Gabe McCallum.
- In Rifts, Baarrtk Krror is only prevented from giving in entirely to hate by his dear friend, Malik Savant.
- The Vampire: The Requiem supplement Danse Macabre introduces the concept of "anchors" as a replacement for the Humanity system. The way it works, essentially, is that you have a set of Morality Chains that prevent you from degenerating and giving into The Beast. You lose an anchor when they become too exposed to the rest of vampiric society or you damage the relationship too thoroughly. Did we mention that the anchor system is meant to be used in conjunction with the Atrocity system and your anchors are the easiest way to safely vent Atrocity dice?
- In Fate/stay night, Ilya is evidently this to Berserker. Note, he's still a massive lump of destructive impulse given terrifying form, he's just better tempered when she's around... unless she orders him to kill someone. Then he gets WORSE.
- Umineko: When They Cry has Hideyoshi Ushiromiya fulfilling this role for his wife Eva. Whenever he kicks the bucket (which happens in every arc), she snaps.
- Dr. Horrible of Dr. Horrible's Sing-Along Blog has two motivations: to Take Over the World and to get up the courage to talk to Penny, the girl at the laundromat. When the Jerkass Designated Hero, Captain Hammer, accidentally kills her with Dr. Horrible's Death Ray, Horrible's closing song makes it clear that he's lost the only thing he really cared about and now there's nothing keeping him from turning truly evil.
- Sylvester, narrator of Twig, plays with this due to his status as a Blank Slate; he allows his friends to define the limits of his morality. When paired with the Token Good Teammates Jamie or Lillian, Sy becomes practically heroic, but when he's partnered with the amoral Mary or the bloodthirsty Helen he will display an almost sadistic focus on causing the enemy the maximum possible harm as they act as The Corrupter to him.
- The Ethics Committee works as this for the entire SCP Foundation. In-Universe, most people at the Foundation consider them comically useless at this, considering all the morally questionably stuff the Foundation gets up to, but several tales and SCPs depict them as highly competent and powerful, sometimes even matching or surpassing the O5 Council in power.
- Eddsworld's 2005 Christmas Special implies that Edd is the only thing keeping Tord from snapping and trying to take over the world. In the Series Fauxnale, it's revealed that Tord being away from Edd for a considerable length of time caused exactly that to happen.