Diabolus ex Machina in literature.
- A rare good use: All Quiet on the Western Front. The narrator is hit by a stray bullet on a day so quiet the official report was a Title Drop. It works because we've already established that Fate is a bitch towards soldiers. It is also an example of Retirony since it happens in the last month of the war.
- Animorphs killed a major character in the finale. Fair enough — their lease on survival was well overdue. But then, not content with successfully leaving realistic loose ends arising from what came before, Applegate brought in a completely unheralded Hindu Borg Collective to really ruin her readers' day in the last handful of chapters. Word of God stated that she felt the fans would have preferred to see the main characters go out fighting.
- In Arrow's Fall, after two books of the protagonist exploring her magic and studying with other mages, it turns out the region she's traveled to has Anti-Magic mushrooms that totally shut down her powers just by existing. And they exist only in the country the Big Bad is occupying. And this is the only time in the entire series that fungi or plants affect someone's magic in any way. And the mushrooms are never mentioned after this plot point again - it doesn't even seem like feeding them to her was deliberate, because the effect wears off before Talia reaches the capital and then her magic is countered by having a guy block it. The mushrooms just exist to make the trip worse for her.
- Battle Magic by Tamora Pierce does this near the ending. After fighting Emperor Weishu's vast armies and actually beating one back from the capital, though with the knowledge that they can't do it forever, everyone suddenly wakes up as Weishu's captive because he's had sleeper agents in the city for decades. The presence of imperial agents wasn't foreshadowed in any way and the previous threat was always the military force. This is the setup for a subsequent Deus ex Machina — literally, the gods of Gyongxe come out and ensure that Weishu won't even think of coming back.
- Bridge to Terabithia: all goes well for Jess, he finally warms up to using his imagination... and then Leslie dies randomly, which drives home the point that cruel reality trumps imagination... The inspiration for Katherine Paterson writing Bridge to Terabithia was her son's best friend likewise being struck by lightning.
- Ellen Hopkins's book Burned throws a completely random car crash to cause an inconvenient miscarriage and kill the protagonist's Love Interest. The author seems contractually required to provide a Downer Ending or Bittersweet Ending because True Art Is Angsty, but all her other protagonists got themselves in trouble with their own actions and not a snowstorm. Note to author: It doesn't count as foreshadowing if you don't foreshadow until five pages before the event!
- Orson Scott Card calls these "dirigible endings;" he once wrote an essay on writing in which he mentioned having taught a writing class where one student had written a story about a cult whose leader had convinced all its members to give away all their possessions and climb to the top of a mountain. The writer then couldn't figure out how to end the story, so she had a dirigible fall on them, crushing them all. Marion Dane Bauer told a similar story in her book on writing; she'd say to her writing students "If you end your story by having your main character get hit by a truck, you have just flunked."
- In Robert A. Heinlein's The Cat Who Walks Through Walls. All fictional universes are real alternate universes in their reality. One of the characters points out that a hero (a writer) is not permitted to resurrect the Big Bad of his favorite fictional universe because of this trope. The character asks if the hero can just retire as head of the training school but apparently the risk is that the story will evolve to need a serious villain, who will come into existence if written.
- The Count of Monte Cristo lampshades and ends up subverting the trope. Initially Dantes blames God and fate for all the terrible things that occurred to him, but with the help of a fellow inmate, is able to reason out how certain people wanted him to suffer, not God. Thus, it becomes a core part of his philosophy that once he breaks out, he can't count on Diabolus to hand out random punishment. It has to be up to him.
- In Meredith Ann Pierce's The Dark Angel Trilogy, Aeriel and Irrylath have finally become an official couple after two years of Will They or Won't They?. So of course it turns out that her body was actually destroyed and reformed into an immortal substance earlier that book, meaning that theirs is now a Mayfly–December Romance. This is Info Dumped by the mentor, who is now a ''voice inside Aeriel's head" who demands that she leave Irrylath and go Riding into the Sunset. Because I Want My Beloved to Be Happy (and wants the world to last longer than “a handful of generations more”), she agrees, and tells Irrylath to go marry the Romantic False Lead. Nobody's too happy about this except the child bard who gets to turn the whole story into a pretty song (and the Romantic False Lead, who is specifically described to be observing the two’s farewell "with barely guarded joy" even though the hero shuts her down pretty quickly).
- Death's End: In the increasingly-wild finale to Cixin Liu's Remembrance Of Earth's Past trilogy, the few surviving characters have escaped the destruction of the Solar System, and it looks like Cheng Xin and Yun Tianming will finally find love across the centuries. Then they happen instead upon some never-before-mentioned "death lines," which just so happen to detonate as they're travelling between planets. This so radically reduces the speed of light that relativistic time dilation causes Cheng Xin and Yun Tianming to miss one another by a few million years. Apparently this is the work of life deliberately aiming to hasten the destruction of the universe, also never before mentioned.
- The Deptford Histories book The Oaken Throne has one of the villains curse Vesper to die surrounded by bells. All through the book he is paranoid of bells ringing. Finally, after all the evil is defeated (and the aforementioned villain is dead), it looks like Vesper's out of danger and there'll be a happy ending. But then the villain's ghost shows up and tricks Vesper into drinking poison, ensuring his curse is fulfilled. The bells? Bluebell flowers rustling in the field around him.
- The Dresden Files book Changes has a very nasty one at the end — after barely managing to win the climactic battle, Harry gets shot and killed. However, it is then subverted in the next book, Ghost Story. Harry arranged for himself to be killed and had his memory of arranging the assassination erased. He did this for extremely good reasons, and the suicide's motivations and consequences are examined in great detail.
- The Epic of Gilgamesh is another of the Diabolus' old-school performances. After Gilgamesh has gone through unbelievable trials to procure a flower that grants eternal life, it's eaten by a snake on his way home. Proof that even the Diabolus ex Machina cannot resist the classic appeal of being Scaled Up...
- Calidore eventually captures the Blatant Beast at the very end of ''The Faerie Queene. Then it escapes and apparently tortures people 'till this day.
- Final Destination: Dead Man's Hand. After the set up disaster the survivors are being transported by a cop, who dies in a freak traffic light accident (the group manages survive the car going out of control though). At the very end of the book the Final Girl, who thinks she's beat Death and won, gets a call from her doctor, who says she has very advanced HIV, contracted from being splattered in the cop's blood at the beginning of the book.
- Hans Christian Andersen, "The Flying Trunk": Things are going well for the beggar guy with the titular trunk with his romance with a princess, until the trunk gets destroyed by shrapnel from celebratory fireworks. Seriously.
- Green-Sky Trilogy: Yay! The children have been found, the last of the old-guard Ol-Zhaan has rendered himself harmless through excessive narcotic use, the Erdling radicals have been jailed, the two races are finally figuring out reconciliation and want to make it work. All we need to do is make this mostly symbolic gesture of destroying the last weapon...oops. Fortunately, Snyder wrote and charted a Canon sequel to her books in video game form.
- Halo: Ghosts of Onyx: Admiral Patterson is down to one carrier and three destroyers, facing two damaged Covenant destroyers. One is taken out, leaving a single Covenant ship utterly defenseless. And then a Covenant fleet 32 ships strong comes out of slipspace between the lone destroyer and the four UNSC ships, and promptly annihilates the human vessels. Made all the more wrenching by the fact that Admiral Patterson had already managed to defeat a numerically superior Covenant fleet, something which even the best UNSC commanders have trouble doing.
- The Hapless Child by Edward Gorey is this trope turned up to eleven over and over and over again. Bonus points for an ending which seems to be headed towards Deus ex Machina but goes with Diabolus ex Machina instead.
- At the end of Harry Potter and the Prisoner of Azkaban it seems as though Harry will be able to leave his abusive foster family to live with his godfather, while the true criminal will go to jail. Then Remus Lupin turns into a werewolf (this being the night just having happened to be a night with a full moon and Remus having forgotten to take the potion, which would keep him safe), and in the confusion, the criminal escapes, meaning the innocent man convicted in his place needs to go on the run rather than take in Harry. Although, it later turns out that to live with the man in question would have compromised Harry's security from potential attackers. Trelawney did predict it a chapter before it happened, but the reader can always hope, no?
- Subverted in the Chronicles of Narnia book The Horse and His Boy. Two lions appear out of nowhere when Bree and Shasta (the title characters) are most hoping to avoid meeting another rider. Then, when they are exhausted from crossing a desert, yet another lion chases them and claws Aravis. When Shasta is lamenting his lion-related troubles to an unseen companion, he learns the truth — the Lion was Aslan, and everything he did was to get them safely to their destination.
- House of Leaves has the moment that Will Navidson, Tom, and Billy Reston finally come upon poor Jed and wounded Wax in the middle of the labyrinth after two weeks, and after Holloway shot Wax. Jed is so happy. Then Holloway reappears and blows Jed's head off.
- The first three books of The Immortals have a pretty cohesive threat - the Emperor-Mage Ozorne has found a way to bring banished Immortal creatures back into the world and does so as part of his attempt to take over the Northern Lands. Sometimes the enemy is his forces, sometimes traitors working for him, and Immortals are mixed in, some good and others bad. Then in the third book he's transformed into a harpy Immortal himself, losing his throne and his own magic in the process, and flees pursued by angry older Immortals. His non-villainous nephew takes the throne in his place and establishes peace with the Northern lands. This seems like the natural end and purportedly it would have been, but then the next book, The Realms of The Gods, comes out. Ozorne has rapidly mastered his new body and magic and got in contact with Uusoae, Queen of Chaos - an entity in opposition to the gods, who's prophecied to one day consume everything - believing that she'll let him rule the Mortal Realms if he helps her to take over. Uusoae was not previously mentioned at all and wasn't mentioned afterwards until The Numair Chronicles.
- I Want to Eat Your Pancreas: While Sakura does have terminal pancreatic cancer, she is optimistic about it. Then, as she was supposed to go meet up with the protagonist shortly after being discharged from hospital, the foreshadowed killer just happens to fatally attack her rather than any of the thousands of other dwellers of their city.
- Roald Dahl does this a few times but James and the Giant Peach has the most egregious example. James lives a happy, contented life until one day his parents are randomly killed by a rhino. In the film version, the death is done offstage, in the following voiceover: "And then, one day, a terrible thing happened. A giant rhinoceros came out of nowhere and gobbled up his poor mother and father."
- The Jungle is made of this, at least until Jurgis discovers Socialism. Even then, the original ending had one of these come out of absolutely nowhere in literally the last sentence of the book to render the entire novel completely pointless. This ending was ultimately cut.
- In Lord Sunday, the final installment of Keys to the Kingdom, Arthur finally collects the 7 Keys. Up until this point, the series has been fairly predictable, although things have been getting kind of real in the background, what with the deposed Trustees being mysteriously murdered and some people dying from plagues. However, it's here where everything truly goes downhill for Arthur. All he wants to do is end the fighting, but the Will has other plans. It uses him to bring in a tide of Nothing to destroy the Universe, because it turns out it's 1/2 of the Architect of said Universe, and wants to die, but it can't until its creation is destroyed. The main characters are frozen by the power of the Keys, unable to do anything to save themselves for the few moments they have until destruction. Fortunately, it gets better. It turns out that they were frozen because the Atlas was recording the Universe for Arthur to recreate it. The catch? Arthur's mother had died just moments before. A series that had been very light-hearted up until this point takes a sudden turn: Arthur went on that entire quest with the only result being the death of his adopted mother. The closing dialogue of the main story? "Wow, Arthur! You won!" "Yeah...I guess we won." Freaking. Ouch.
- The Kite Runner, by Khaled Hosseini. The protagonist and his best friend's son are getting along well and all set to move to America when the main guy tells the boy he might have to go back to the orphanage for a short time, and the little boy tries to commit suicide and stops talking.
- Tom Holt has a good working relationship with the Diabolus. This is particularly exemplified in Little People, where he introduces an entirely new metaphysical rule just to ensure the Downer Ending.
- The ending of Malevil tastes a little of this, because of a Distant Finale. Some 575 pages are spent on a six-eight month period and the final 20 pages are a 3-year epilogue. More tragedy strikes in the final pages then the whole novel before because it covers a much larger span of time, bringing the story to a Bittersweet Ending.
- In Midnight's Children, Ahmed and his business partners are told "Shame If Something Happened" and must make a payment. When they go to deliver it, a monkey comes out of nowhere and tosses their money sacks in a gutter. This forces Ahmed to relocate to Bombay, which sets many events in motion.
- In the novelization trilogy of Mobile Suit Gundam, Char Aznable is able to convince Amuro Ray to join him and help end the One Year War. Even more, he warns them of the Solar Ray weapon Gihren Zabi has aimed at A Baoa Qu and Amuro races off to warn the crew of the Pegasus IInote and the other Federation soldiers of these developments. Cue one of Char's wingmen getting too trigger happy with his Rick Dom and shooting the G-3 Gundam in the back, blowing it up and killing Amuro.
- The New Job has, as its title would suggest, a main character whose life is marked by suffering and reversal. Some of the nasty events come with a bit of advance warning; others, including a literal plague of locusts, come out of left field.
- At the very end of "Nuclear Holocaust Never Again," the second book in the "Never Again" series by R. J. Rummel, things are looking pretty good. The heroes have managed to Set Right What Once Went Wrong and have confronted the parents of the at-this-point still an infant villain, who have willingly let the heroes adopt him so that he doesn't grow up to become a nuclear-war-causing dictator. Then, John, Joy, and the child are blown up by a religious extremist's bomb. At least the world is safe, until the sequel anyway.
- Proof that the Diabolus has been around for a long, long time exists in the ancient Greek myth of Orpheus, the bard, who walked into Tartarus to bring back his wife, Eurydice, who had died on their wedding-day. After giving a performance that made the Furies weep, Hades gave his permission for Orpheus to bring her out with him — so long as he walked all the way out without turning around and looking back. The catch? Nobody told him he had to wait before both were outside... For a second, he sees her shade, before she is pulled back to the underworld, crying his name... Some versions of the myth have the Diabolus in another guise and have him lose his nerve for some other reason; thinking that he heard her cry out, for instance, or just plain ol' lack of willpower.
- Swedish writer Simona Ahrnstedt does this in her debut novel Överenskommelser. Beatrice and Seth, the two protagonists, have what can only be described as a really hot date. Surely they will sort things out now, after eight months of misunderstandings? Surely now Beatrice won't have to marry Rosenschiöld (who's like forty years older than her and treats women like dirt), to whom she was forced to get engaged? But alas, not only does she have a tyrannical uncle. She also has a sadistic sociopath for a cousin, who now makes sure that she's separated from Seth. Cue a whole year of more misery for Beatrice...
- Perdido Street Station by China Miéville's summons the Diabolus ex Machina with an unholy ritual of Dungeon Punk Thaumaturgy. The fact that two completely separate incidents, with no relation between them, ensures that all the main characters will spend the rest of their days being utterly miserable makes this one of the nastiest examples of the demon's works. Deus Angst Machina was invited to the party, and danced all night long...
- Mieville's other books, Iron Council and King Rat, do this to a lesser extent. The first involves one of the main characters doing something incomprehensibly stupid that denies the revolution against the tyrannical government of New Crobuzon much-needed reinforcements (though it's implied they wouldn't have won anyway). The second has the reader being informed casually that the children who were the original victims of the Big Bad of the story were condemned eternally to hell alongside him (and the main character essentially doesn't care). Iron Council even has the chutzpah to tack on an epilogue that tries to make it not seem like the complete and utter betrayal that it is. The author has said a happy ending would be a betrayal to reality and the everyday suffering of the oppressed. He believes life is a continuous stream of Diabolus Ex Machina.
- Jodi Picoult:
- At the end of My Sister's Keeper, Anna finally gets medically emancipated from her parents... and is then killed in a car accident, yet her kidneys — the organ she had been asked to donate earlier in the book, leading to the aforementioned emancipation quest — are perfectly intact to give to her sister, rendering her actions pointless.
- At the end of Handle with Care, after an long, grueling trial initiated to gain funds for Willow's treatments, the O'Keefe's win the trial and the money, and immediately after, Willow drowns in the icy lake behind her house, rendering the trial pointless.
- "The Pit and the Pendulum" uses both this and Deus ex Machina. The narrator is about to fall into a pit in the middle of the shrinking room, and the contents are so horrible he cannot find words to describe. Then, in the last few sentences, his arm is caught by a friend.
- The Princetta: The main characters return from their adventures and are all set to live Happily Ever After, Malva and Orpheus get together... and then Orpheus is murdered at the last minute.
- The Ramayana: AFTER Rama rescues his wife Sita, wins the epic battle against the demons, and gets crowned king, he puts her through not one but two trials by fire. Because his subjects believe she might have cheated on him while she was being held hostage. She asks to be — and is — swallowed up by the earth after trial by fire #2. This last part is usually omitted in retellings for good reason.
- The Reynard Cycle: In Defender of the Crown, Reynard foils a conspiracy to kill the Queen by drugging her with a sleeping potion that causes her to appear as though she were dead. When the conspirators attempt their coup, he's waiting for them. Problem is . . . He inadvertently poisoned her, she's actually dead, and this information is revealed in a room full of witnesses who now need to be silenced. Some of whom are children.
- Seeker Bears, by Erin Hunter. A young polar bear, Kallik, is orphaned and alone. After much wandering and hardship she gets caught by humans, who plan to re-release her alongside Nanuk, a mother who'd lost her cubs, in the hopes that she would adopt Kallik. After some consideration, both bears decide that this is an acceptable arrangement. Nanuk immediately dies in a helicopter crash.
- The end of Part 1 of The Sex Gates. Lee and Rita are going to have a baby, Rita is finally opening a facility that should make the lives of technologically-deprived poor people much better... and then one of those same poor people fatally stabs her when he's supposed to be shaking his hand. They're forced to push Rita through one of the titular gates, which saves her life at the expense of turning her into a man and destroying her unborn child in the process — and Lee loses his balance and falls through as well, turning into a woman.
- Shows up in Shiver in the form of a white-tailed deer. It appears in the middle of the road at exactly the wrong time, causing the crash that wrecks Grace's car. Both occupants survive, but with no way to keep Sam warm until help comes, he turns wolf for good. The characters are forced to try an incredibly dangerous plan to bring him back.
- Star Wars Legends: So the New Republic has made peace with the Imperial Remnant, the Jedi's image has recovered somewhat from Darth Sidious's propaganda and from Luke Skywalker's mishandling of Caridagate. Black Sun is too busy licking its wounds to be any threat. Sure, there are still some interplanetary troubles, just like there were in the Old Republic, but nothing the Jedi can't — What the kriff? There's been an implacable extragalactic invasion force massing at the edge of the galaxy since about the time Sidious became Chancellor?
- What's that? The weird little alien who was a teacher to Jacen was really a Sith and was setting him up to be turned to the Dark Side? And it worked, years later?
- And despite his death being one of the most critical moments in the whole franchise, Palpatine is revealed to be effectively immortal, as he can now transfer his essence into almost anyone (particularly the army of clones of himself he just had lying around). And now he's ready to cement his status as the most powerful force user of all time by turning Luke to the darkside, being able to transport anything anywhere or any time, and destroying entire planets and fleets with a newly invented "Force Storm." That's right, he doesn't need a Death Star.
- The ending to Volume 7 of The Unexplored Summon://Blood-Sign. Kyousuke has created the Colorless Little Girl, an artificial summoned being designed specifically to defeat his nemesis, the White Queen. The Colorless Little Girl utterly curb-stomps the White Queen, and appears to successfully kill her once and for all. On top of that, Kyousuke manages to settle the score with his father. And then the White Queen reappears, having somehow survived. To make matters worse, she reveals that this was All According to Plan. By allowing the Colorless Little Girl to defeat her, she's ensured that the Girl will be warped into a monster greater than the Queen ever was (this part isn't an Ass Pull, as the concept was established earlier in the series). To defeat the Colorless Little Girl, Kyousuke will have no choice but to work with the White Queen... meaning that she's finally achieved her goal.
- At the end of Knut Hamsun's Victoria, it looks like Johannes and Victoria will finally get a chance to live out their love, but Victoria suddenly gets tuberculosis and dies.
- In Warhammer 40,000: Gaunt's Ghosts, Lijah Cuu is effectively a manifestation of Diabolus. At the end of The Guns of Tanith, he kills off "Try Again" Bragg. In Sabbat Martyr, although the fighting is effectively over and the nine chosen assassins have been slain, he is subverted by Chaos psykers into killing Saint Sabbat. Although he does not succeed and dies in the process, he still succeeds in killing Colm Corbec before he gets killed too.
- Poor Sehra Muril, the red-haired girl with a "deliciously dirty laugh." She was going to be first FEMALE VERGHAST SCOUT if it hadn't been for Cuu!
- Wars of the Realm ends with a Post-Climax Confrontation between Validus and his archenemy, Niturni. Validus fights Niturni into a Sword-Over-Head situation, but hesitates just a little too long to finish him off. This sets up the death of Validus' best friend, Persimus, who translates from the human realm back into the Upper Realm to take Niturni's sword for Validus. In hindsight, Niturni's appearance kind of makes sense, given his explanation to Validus. BUT Persimus could just as well have backstabbed Niturni or at least come in earlier and made Validus' fight a two-on-one instead of just taking the blade.
- Ian Irvine goes all out in his Well of Echoes trilogy (which became a quadrilogy almost, it seems, so Diabolus could strike). The world is saved! All is harmonious! At which point one of the Big Bad whose son explicitly identified him as dead earlier turns up. To top it all off, the heroes then destroy all the world's magic, hoping to overload his personal magic source, but that backfires, leaving him the only one with any real magic in the entire world and the rest of civilization pawns to his whims. All so the author could go on and write a dictatorial dystopian trilogy as a follow up. Go figure.
- The author loves his cliff hangers, with only one of his fantasy books actually having a proper, satisfactory ending. The others have such glorious situations as one character inadvertently summoning an interdimensional invasion force to her world, the magical field failing at a pivotal battle, rendering the vital magically powered walking tanks useless in the face of a horde of giant winged and clawed mutant monster things, and all the protagonists being captured by a Big Bad and sentenced to be flayed alive. No happy endings here, folks.
- In the last The Wheel of Time, despite setbacks, the good guys are actually winning — and then Demandred shows up with a massive Sharan army, which by the way has more channelers than the White Tower, Black Tower, Aiel, Sea Folk, and Seanchan combined.
- In The Zodiac Series, Rho has finally convinced the Plenum that Ophiuchus is real, and the entire Zodiac forms an armada to go after him...and then an entirely new enemy shows up called the Marad, who wipe the floor with the armada and kill Mathias. It was foreshadowed a few chapters before the event, but still, ouch.
- The third book, Black Moon, also has an example. It looks like the heroes have managed to outwit the Master, having organized the Guardians into a group devoted to searching for him. Nope. Turns out Aquarius saw this coming, took the opportunity to revive Ophiuchus for real, and the book ends with a Cliffhanger and Stanton dying.
