Hercules capturing Cerberus, 1545, by Sebald Beham

Cerberus (Kerberos), the hound of Hades, is a legendary three-headed dog of Greek and Roman mythology. Like his counterparts the four-eyed Norse dog Garmr and the jackal-headed Egyptian god Anubis, Cerberus is the guardian of the gates of the Underworld, tasked to keep out the living and keep in the dead. His back is covered by a mane of snakes, and his tail is described as being that of a dragon or a snake.

Like many Greek monsters, Cerberus is descended from Poseidon (Neptune), brother of Zeus (Jupiter) and god of the seas. (He is Poseidon & the Gorgon Medusa’s great-grand-dog.) Cerberus is the offspring of the Enchidna, a half-nymph, half-serpent monster who is also the mother of the Hydra, the Chimaera, and the Sphynx, among others. While most sources describe Cerberus as three-headed, some speak of fifty heads or more. But it is possible that the extra heads sometimes mentioned are those of the snakes that make up his mane.

Fluffy sleeping in Harry Potter and the Sorcerer’s Stone. In the film, the nationality of the person Hagrid acquired the hellhound from was inexplicably changed from Greek to Irish.

The final Labor of Hercules (Herakles) was to bring Cerberus up from the Underworld. Hercules first asked permission from Hades (Pluto), Cerberus’s master and Lord of the Dead. Hades allowed Hercules to take Cerberus, but only if he were able to capture the fearsome dog-monster using no weapons. After accomplishing his task, Hercules sent Cerberus back to the Underworld gates to resume his guard dog duties.

“Cerberus, crouching in his cave, howled with all three heads. Upon seeing the snakes entwining his necks rise with anger, the Sibyl tossed the dog a cake soaked with sweet honey and sleep-inducing drugs. Greedily, all three mouths swallowed the sweet food, and the monstrous dog immediately fell asleep.”   —The Aeneid of Virgil

As with many characters of Greco-Roman mythology, Cerberus is well represented in astronomy. There is a constellation, an asteroid, and a moon of Pluto all named after him. A spot on the surface of Mars is also named Cerberus—which is fitting, as it is believed that the name kerberos is similar in meaning and usage to the modern dog name “Spot.”

Cerberus in Popular Culture

MLP:FiM Cerberus

Cerberus appears in two episodes of My Little Pony: Friendship is Magic. He has red eyes, and most closely resembles a bulldog in breed. When Cerberus appears in Ponyville, Fluttershy is able to calm him by rubbing his belly, and Twilight Sparkle lures him back to Tartarus with a toy ball, easily supplied by Pinkie Pie, who keeps them stashed all around town in case of just such a “ball emergency.”

Fluffy is the name of the three-headed guard dog in Harry Potter and the Philosopher’s Stone. Fluffy’s breed most closely resembles that of a Staffordshire Terrier. He is one of Hagrid’s many pets, and was set to help guard the Philosopher’s Stone during Harry’s first year at Hogwart’s. Fluffy was acquired by Hagrid from a Greek man at the Leaky Cauldron, and Fluffy is in fact eventually sent back to Greece by Dumbledore after the stone is destroyed and Fluffy’s service is complete. As with Cerberus in the legend of Orpheus, Fluffy can be lulled into sleep by the playing of music.

Animaniacs’ Cerberus & Satan

A Boxer-like version of Cerberus appears in the Animaniacs when the Warners accidentally meet Satan (voiced by Ron Perlman) in Hell while trying to find their way to an amusement park.

The Smoke Monster/Man in Black of the television series LOST was referred to as “Cerberus” by the DHARMA Initiative, perhaps because the monster appeared to be a subterranean-dwelling guardian of some kind.

Cerberus also appears in games, several Marvel comics, and many books, films, and television series. Cerberus does not speak in human language, and has no human behaviors. What we love about Cerberus is that at heart, he’s really just a dog. A huge, scary, three-headed dog, but still a dog.

“The tongues of hell
Are dull, dull as the triple
Tongues of dull, fat Cerberus
Who wheezes at the gate.”

—Sylvia Plath, “Fever 103°”