The trope of the Friendly, Playful Dolphin has become so well-known in recent years that it has become popular for writers of various works to subvert it by instead depicting them as cunning, sinister, and even evil animals — in essence, an Alternate Character Interpretation of them as species. This is mostly found in comedy works, much like the similar Hair-Raising Hare trope, which also relies on subverting the audiences expectations of a typically "cute" animal.
Ironically, this trope is actually closer to reality than the one it began as a subversion of, since recent research has shown that bottlenose dolphins often display behavior that would be considered sociopathic by human standards, including a tendency towards violence and recorded instances of infanticide and aggression towards other cetaceans. Chances are, though, that most of the writers using this trope were not aware of that fact, although some probably are.
Orcas, aka killer whales, which are actually a species of dolphin despite their name, also often fall under this trope. While they do not have the violent social interactions of bottlenose dolphins, the fact that they feed on seals, penguins and other dolphins makes them common antagonists in stories about sea animals when sharks aren't being used. And even then orcas will play this on the occasion the shark is a protagonist, due to the fact orcas also eat sharks. However, like "typical" dolphins, they're equally likely to be depicted as cute and friendly.
Contrast Heroic Dolphin and Friendly, Playful Dolphin. Compare Monstrous Seal and Wily Walrus for other dangerous sea mammals, and Maniac Monkeys for another "evil" take on a normally cute animal noted for its intelligence.
- In episode 1 of Problem Children Are Coming from Another World, Aren't They?, You Kasukabe mentions having met aquarium dolphins who are jerks. At least, only in the English dub.
- The 1977 film Orca: The Killer Whale centered around a violent, unnaturally aggressive killer whale. It's depicted as both intelligent and vengeful, playing into the stereotype of dolphins as the animal version of an Evil Genius.
- In The Pebble and the Penguin, orcas are portrayed as The Dreaded, not once coming across as friendly or playful. In fact, their behavior is more in line with killer whales in real life.
- Alastair Reynolds' Chasm City uses this trope by means of Subverting Friendly, Playful Dolphin. The first of the Sky Haussman flashback episode introduces you to children Sky and Constanza who evade their parents' oversight to go visit the dolphins who are kept in the spaceship they live in. That looks very cute and slightly cliché... until you meet the dolphins, who after being used as experimental subjects by a radical transhumanist group and then kept and bred in captivity for centuries, have turned sadistic and totally psychotic.
- The Scar: Dolphins are an intelligent race in the setting. The main dolphin character in the book, and also the head of the underwater police of the floating city of Armada, is a vicious sadist named Bastard John.
- Cthulhu Mythos
- In H.P. Lovecraft's short story The Temple; the protagonist's submarine is followed/escorted to a mysterious undersea city by a large number of dolphins.
- In James Wades The Deep Ones, dolphins are minions allies of the Deep Ones and described as "evil servants of evil Old Ones, malevolent, toothy-smiling hypocrites".
- Mystery Science Theater 3000: In Devil Fish, Mike and the bots decide they dislike dolphins. They call Sea World in order to mock Blowie the Dolphin over the phone. And then a dolphin warship appears outside and fires at the Satellite of Love, and doesn't leave until Mike apologizes to Blowie.
- Walking with Beasts features an episode ("Whale Killer") centered on the Basilosaurus, a prehistoric, carnivorous whale with massive teeth. Various other predatory cetaceans are shown as well.
- In the mythologies of many of the native peoples of the Amazon Rainforest, the Amazon River dolphins, also called the encantados, are given many characteristics reminiscent of The Fair Folk — while they're not understood as being actively malicious creatures, they're still treated as potentially very dangerous. They are often described as stealing away people they meet on the river shore (or on dry land, as they're also said to be able to take human form), who will be taken to the dolphin's magical realm below the waters and never seen again. In some places, this has resulted in people refusing to go near the river at night or alone. Encantados are also attributed with other harmful powers, such as causing insanity and spreading disease.
- Dolphins are typically not personified in Polynesian myths, being considered basically marine livestock. This is not the case for the Caroline Islands people, which depict them as sexual deviants.
- Call of Cthulhu supplement Cthulhu Now, adventure "The City in the Sea". While searching for an underwater temple, the Player Characters are attacked by a group of killer dolphins under the control of a Cthulhu Mythos deity named Gloon.
- Dungeons & Dragons: The Frostburn sourcebook includes the Malasnyep, a species of typically Chaotic Evil dolphin-like monsters native to the far north. They are viciously aggressive and will attack anything that cross their path, seemingly doing so entirely out of a compulsion to kill anything that enters their territory.
- Coak in Transhuman Space is a Boomerang Bigot uplifted dolphin who runs a ruthless terrorist group dedicated to the eradication of Uplifted Animals.
- Ecco the Dolphin: Defender of the Future: The Clan is a group of wicked dolphins who torture and mutilate animals and believe in dolphin superiority, though only for their own faction: they torment Outcast dolphins just as gleefully.
- Hungry Shark World: The dolphins are sinister creatures who look flat out evil, with sharp teeth, and they will try to eat your shark.
- In Karin's Skin Diving Diary!, the dolphins aren't exactly devious or violent, per se, but definitely annoying to encounter, as all of the fish you attempt to catch will swim away while a dolphin is onscreen. You're forbidden from catching dolphins, as they will penalize the player by subtracting 20% from their current score. You either have to scare them away with a Fuel Stone (at the risk of scaring away other valuable fish in the process), or catch them anyway to get rid of them and make up for your lost points afterwards. What isn't helping their case is that they're more likely to appear if a squid is onscreen.
- Dolphins in Kingdom of Loathing are found in ocean zones, and are utter jerks that have a huge tendency to steal items dropped by monsters after a battle. You can get your items back by using a dolphin whistle and beating up that rotten dolphin thief.
- Plants vs. Zombies has the dolphin that the Dolphin Rider Zombie rides on. The dolphin is also a zombie, aids its owner to get to your house and eat your brains, and can help the rider jump over the first plant it encounters that isn't a Tall-Nut.
- Sonic Adventure features an extremely aggressive orca that chases after Sonic in Emerald Coast, destroying a pier in the process. Sonic the Hedgehog (2006) also has a hostile killer whale in Wave Ocean.
- Command & Conquer: Red Alert 2 sees the Allies use specially trained attack dolphins carrying a Wave Motion Gun to counter Soviet mind-controlled Giant Squid. They're friendly towards the player controlling them, devious towards anyone else.
- Wadanohara has an orca who seems to delight in menacing sharks and seems to particularly enjoy fighting. Although Sal is technically a shark disguised as a dolphin for most of the game, said disguise gains red eyes after he reveals his intentions.
- The Adventures of Dr. McNinja: Agent Bearclaw used to pretend to be drowning, just so he could kill the dolphins who came to rescue him. So when he falls into the ocean after a real plane crash, and more dolphins show up, he assumes they're here for revenge and panics. But in spite of his fears, the dolphins actually carry him to a nearby island. Relieved, Bearclaw thanks the dolphins for their mercy... and then the dolphins pull out guns and shoot him.
- In Awful Hospital, dolphins are literally the stuff of nightmares in the Perception Range. When one shows up, it's a nigh-unstoppable Juggernaut that creatively mutilates its victims and can punch through a steel bulkhead. They also reproduce via Chest Bursting and selectively edit themselves out of people's memories, making them full-on Animalistic Abominations.
- Cracked had an article on how dolphins have been observed committing rape on each other.
- Mortasheen: The creator is fully aware of the fact that dolphins are aggressive, often vicious predators who exhibit behaviors that humans would consider cruel, depraved and sadistic, and finds their portrayal in fiction as friendly and heroic beings boring and overused; as a result, whenever you see a Mortasheen monster based on a dolphin, you can immediately expect something extremely cruel, depraved and horrific even by the standards of the setting:
- Dolfuries, also called the Slaughtering Cacklers, are some of the very few Always Chaotic Evil monsters. They were originally created as human-dolphin chimeras to be guard monsters for the vampires, which resulted in "combining the intelligence and cruelty of both hominid and delfinid". The result were creatures that were unspeakably sadistic, monstrously cruel, borderline sociopathic and easily bored. Their vampiric creators tried to destroy them all out of disgust, but one female escaped with her offspring and they've been plaguing the world ever since.
- Cacchinnoxes are a kind of Joker — brightly colored, clown-like monsters who live in hives and lead lives of anarchism and destructive "humor" — resembling enormous, eyeless dolphins that move around on dry land by slithering on their lower bodies. They can also tune their squeaks to cause intense pain to their victims. Their sense of humor is cruel even by Joker standards, inevitably focusing on causing physical or emotional harm on whoever is unlucky enough to become the target of the Cacchinnox's comedy, and as a result even other Jokers are forced to keep them contained deep within their hives.
- Obliviotes are incorporeal psychic parasites that drain the intelligence of their hosts "until the victim is little more than a vegetable". It is essentially a carbon copy of the Thought Eater from Dungeons & Dragons (one of the creator's favorite monsters from that game), palette-swapped from a platypus to a dolphin to crank up the disturbing factor.
- The YouTube series "Scientifically Accurate" portrays dolphins as tragic, but sometimes evil, in "Scienticfically Accurate Flipper".
- The Loan Dolphin from SuperMarioLogan is a dolphin whose job is a debt collector. He wears a leather jacket and speaks in a gruff voice, but he's only an antagonist to those who don't pay their debts. In the episode, "Bowser Junior's Lemonade Stand!", when Junior hires the Loan Dolphin to destroy Cody's lemonade stand, he refuses, since he thinks it looks nice.
- Elena of Avalor has the Malandros, which are for all intents and porpoises accurate depictions of the Amazonian boto myth.
- One episode Kenny the Shark features an orca named Buster, who acts friendly towards Kat and the other human characters but is a vicious bully towards Kenny due to orcas being predators of sharks. Eventually, Buster turns hostile towards Kat as well, which causes Kenny to lose his fear of the orca and stand up for her.
- My Gym Partner's a Monkey has two dolphin characters, both of whom are mean. Phineas is an Insufferable Genius who bullies anyone who is not his teacher nor part of his posse, and Donna is an Alpha Bitch in Sheep's Clothing.
- In The Penguins of Madagascar, Dr. Blowhole is a recurring antagonist. He is a dolphin with a mechanical right eye who used to work as a performing dolphin in a marine park. He wants revenge on the humans for the humiliation that lead to his path of villainy, and he refers to the Penguins as the "Pen-gyu-ins".
- The Simpsons:
- In "Boy-Scoutz 'n the Hood", Bart, Homer, Flanders and Flanders' kids remain stranded at sea after getting lost while rafting. They're eventually approached by a trio of dolphins. Flanders is relieved, stating that dolphins always help people lost at sea. Instead, the dolphins merely chitter to each other that the castaways are all going to die, laugh a bit, and then leave them to their fate.
- In the "Treehouse of Horror XI" segment "Day of the Dolphin", an aquarium dolphin named Snorky leads the rest of dolphinkind to rebel against the humans, take back the land for themselves, and force humanity into the sea to die.
- Subverted in South Park, where it turns out the reason the Japanese whaling industry (represented by a screaming mob of Japanese people showing up to murder captive dolphins and whales — sorry, dorufins and werrus — with sharp objects) exists is to avenge the atomic bombings of World War II (the American government having released photos that showed both cetaceans piloting the Enola Gay). By the end of the episode, Kyle explains the truth to them: the true people responsible for the bombings are a chicken and a cow.
- Zig & Sharko: The minor character Insane Dolphin, although not evil per se, is as his name implies severely unhinged. He's apparently a trained military dolphin who mistakes civilian ships and random geographical features for enemy aircraft carriers, and throughout both of the episodes he appears in constantly attempts to sink everything he comes across with the never-ending supply of mines he keeps on his person. Both of his appearances culminate in him sinking the island the main characters live on and sending everyone on it to Fluffy Cloud Heaven.
- It's been theorized that the stories of drowning men pushed ashore by dolphins might be biased: sure there are people who were pushed towards land, but how many were pushed away?
- Real Life dolphins are known to be much more prone to aggression than their popular culture depictions show them as: among other things, Atlantic bottlenose dolphins have been repeatedly recorded mobbing porpoises and beating them to death. Why they do this isn't clear — they don't eat the corpses afterwards, and while competition for food was brought up as a possibility the two cetaceans don't seem to feed on the same types of fish.
- Orcas are naturally macropredatory dolphins. And if you consider river dolphins as such (they're actually several different lineages of unrelated toothed whales), then several extinct relatives of these were basically mammalian pliosaurs, such as the aptly named Squalodontidae (literally shark toothed).