The "monster of the week" episode is an endangered beast. Once upon a time, television was full of single-episode stories, in which the heroes faced an unstoppable threat and won, all in about 43 minutes. Here are 10 "monster of the week" episodes that pack more storytelling power than a season-long arc of most TV shows.
Note: To help narrow things down, let's set a few conditions. We'll only include standalone "monster of the week" episodes where the monster in question appeared only once, and was never heard from again. So for example, Doctor Who's "Blink" is disqualified since it was arguably the first episode in a long-running arc involving the Weeping Angels. With that out of the way, here we go...
10 Terminator: The Sarah Connor Chronicles, "Self-Made Man"
When the Terminator TV show started, the creators said they wouldn't be doing "Terminator of the week" episodes — but then they did just one, featuring a random Terminator who goes back in time to kill a politician and overshoots, becoming Myron Stark, a big wheel in the 1920s gangster scene. Cameron, the friendly Terminator, figures out that Myron Stark is coming back, and manages to be there to greet him. It's a lovely, creative take on Terminator lore that uses time travel in a uniquely clever way.
9 Red Dwarf, "Polymorph"
It's sort of a weird version of Alien set on the Red Dwarf, in which the crew is hunted by a shape-shifting creature that steals their negative emotions to sustain itself. And it's often mentioned as one of the best Red Dwarf episodes, because the monster radically changes all of the characters and their dynamic winds up becoming very different before they deal with the monster. Often, the best monster-of-the-week episodes are the ones that change the regular characters in some way, or help us see them in a new light.
8 Cowboy Bebop, "Pierrot Le Fou"
This is the one where Spike gets his ass kicked, by a killer who targets him after Spike sees Pierrot commit a murder. Spike and his crew have to figure out who Pierrot is and what his weakness is, before he finishes the job. We discover that Pierrot is the result of strange experiments, which turned him into this abomination. This episode gets a lot of praise for its amazing visuals and intense atmosphere — but also for putting Spike in a position where he's already lost a fight at the beginning of the story, for once.
7 Xena, "A Day in the Life"
The monster this time around is the world's biggest giant, who's going to crush a village, and meanwhile some bandits are going to raid another village. But really, it's about exploring the Xena-Gabrielle relationship, while also introducing us to Minya, a young woman who feels threatened by Xena's awesomeness. In the course of the story, Xena has to outwit the bandits and giant while also empowering Minya — and the giant, whom we only meet this one time, is a particularly great foil in an episode about outsized personalities.
6 Supernatural, "What Is and What Never Should Be"
This is the one where a Djinn traps Dean in a dream world wherehe has everything he ever wanted, including his mother back from the dead. Like a lot of the episodes on this list, it's about illuminating the characters, as a way of presenting them with an even bigger no-win situation.
5 Star Trek, "Where No Man Has Gone Before"
The "monster" in this episode is Captain Kirk's friend Gary Mitchell, who gets godlike powers after being bombarded with a strange energy — and Kirk has to sacrifice his friend to save the ship. The real focus is the interplay between Kirk and Spock as Spock tries to convince Kirk that sometimes you have to make the impossible choice for the good of everyone else. Never does Spock seem more chillingly emotionless.
4 Angel, "Smile Time"
We praise this episode a lot — but it really deserves all the praise. Ben Edlund's hilarious story of Angel being turned into a puppet actually features a great monster, in the evil puppets that try to suck the life essence out of children through their television screens. It's one of the show's most fun episodes, but presents Angel with a unique adversary during his "tool of the man" phase: cute puppets that use mass media to get their own way.
3 Doctor Who, "Midnight"
The fact that we've never met the creature from this episode again, or learned more of its secrets, is part of why it still has so much power. The Doctor is on a tourbus in the middle of nowhere, when one of the passengers becomes sort of possessed by a mysterious presence — and then it targets the Doctor. Like most of the episodes on this list, this shows the Doctor in an extreme situation that paints him in a new light, but it's also an intense tale in which there's no easy win.
2 The X-Files, "Jose Chung's From Outer Space"
We almost put "Tooms" here, because of intense horrible creepiness — but Tooms actually appears in two episodes. And Jose Chung does feature a monster of the week, the alien that's abducting fake aliens. The whole thing is the setup for a strange metafictional tale, in which Jose Chung gives us a very different look at Mulder and Scully, and their entire world. Check out Crave Online's great exegesis of why this might be the best X-Files episode.
1 Buffy the Vampire Slayer, "Hush"
We had to put this up top, because the Gentlemen are another great example of a monster that never reappears and starts getting overexposed or overexplained. They show up, steal the voices of everyone in Sunnydale, and nearly complete a terrible ritual — until Buffy and Riley figure out a way to stop them. In a show that's all about characters who have the gift of gab, using their voices to figure out everything together, the nearly silent episode is the creepiest thing ever.
So what did we miss?
Thanks to Genevieve Valentine for the input!