Beware of Vicious Dog

Everything About Fiction You Never Wanted to Know.
Nice doggy...good doggy...
Sign found on a Roman house, proving that this trope is Older Than Feudalism

This is where a dog is really, really mean to anyone and everyone, anything and everything, whether rabid, genetically tampered with, or trained from birth to be that way. If the dog has an owner, then sometimes even the owner can get on the dog's wrong side from time to time.

This type of dog is not a Hell Hound, but is a rather normal and standard dog aside from his viciousness. He CAN be kicked, but 9 times out of 10 Failure Is the Only Option where that is concerned. Indeed, kicking him successfully will often make you look reasonable.

NOT a Big Badass Wolf, though given his temperament, he may as well be.

May be an Angry Guard Dog or a Bully Bulldog, although those types usually guard homes or properties. The Vicious Dog, on the other hand, is mean regardless of his size or breed and regardless of whether he's a pet/guard dog or not.

The Evil Counterpart of the Big Friendly Dog.

If a Big Friendly Dog or a dog that's normally a Gentle Giant gets infected with rabies or is genetically tampered with, chances are very good that he'll become this. In which case, BE VERY AFRAID.

The trope takes its name from the frequent signs on the front of homeowners' gates, usually reading simply "Beware Of Dog," that warn visitors about the potential badness of the resident pooch.

Examples of Beware of Vicious Dog include:


  • The poodle in There's Something About Mary. Played for Laughs.
  • "The Beast," the giant Mastiff dog in The Sandlot, who terrorizes the land next door to the titular sandlot where the kids play baseball, to the point that he's become something of a legend and the kids have to take great care not to knock their baseballs over the fence to where he is; getting back a Babe Ruth-signed ball drives the second half of the movie. Subverted--he turns out to be a Gentle Giant once the kids get to know him.
  • The sled-dog Demon in Snow Dogs behaves this way due to a sore tooth.
  • Max, the Tibetan Mastiff in the 1993 film Man's Best Friend, is this due to being genetically enhanced.
  • The 1977 film The Pack is about a group of dogs that behaves this way.
  • The 2006 horror movie The Breed has the protagonists being stalked by a group of dogs that embody this trope.
  • Chopper, Milo Pressman's dog in Stand by Me, has this reputation. Subverted.


Jamal: I believe in free will. If my dog wishes to hate everyone in the world but myself, it is free to do so.

Live-Action TV

Video Games

  • Shadow's dog Interceptor in Final Fantasy VI, only being obedient to Shadow himself and nice to Relm on their first meeting.

Shadow: Leave us. The dog eats strangers...

Western Animation

  • Oscar the dog from Kick Buttowski.
  • Gru's... dog?.. thing from Despicable Me, who strikes fear in everyone, even its master. That is until Agnes comes along.

Other Media

  • Popular parody: Picture of a firearm. "Forget the dog, beware of the owner."

Real Life

  • This news report. (It's where the trope image comes from.)
  • Truth in Television where dogs who are trained and bred to fight are concerned. Rottweilers in particular have gotten a bad reputation for being vicious because of this.
  1. Beware the dog