1 of 10
Season 9, episode 20
The Supernatural spinoff didn't quite live up to fans' expectations, and although it probably didn't deserve all the hate it received, it doesn't quite measure up to other hours. Bottom line: It's hard to compare when the hour is severely lacking in Sam and Dean (even though that's on purpose). —Samantha Highfill
2 of 10
9. ''The Mentalists''
Season 7, episode 7
More forgettable than it is truly terrible, ''The Mentalists'' just doesn't have much going for it. There could be a lot to play with when considering the most psychic town in America, but the sibling ghost issues at the heart of the mystery are just lame. And the episode may mark the quickest turnaround for Sam and Dean fighting and then reconciling, which sucks all the drama out of Amy's death. —Jonathon Dornbush
3 of 10
8. ''The Slice Girls''
Season 7, episode 13
Wonder Woman would definitely not want to be associated with these Amazon warriors. After going home with Dean one night, the secret Amazonian Lydia becomes pregnant and, in the blink of an eye, gives birth to a daughter. The only problem is that she's destined to kill her father. So Sam makes the difficult choice for Dean and kills the child in one of the series' most uncomfortable and unsavory moral dilemmas. —Jonathon Dornbush
4 of 10
7. ''Route 666''
Season 1, episode 13
In a not-so-memorable hour, the brothers are forced to face off with a black truck that keeps running people over/running them off the road/generally killing everyone in its path. Bringing in Dean's ex is a nice touch, but it doesn't take away from the whole haunted-black-truck thing. All in all, the episode lacks an edge. —Samantha Highfill
5 of 10
6. ''Mannequin 3: The Reckoning''
Season 6, episode 14
While Dean heads off to explain to Ben that Lisa going on a date isn't an ''emergency,'' Sam is left to work a case involving a dead sister, a kidney transplant, and a lot of mannequins. Of all the things to haunt, mannequins just aren't scary. And neither are kidney transplants. Plus, brother separation is never ideal. —Samantha Highfill
6 of 10
5. ''All Dogs Go to Heaven''
Season 6, episode 8
Sam and Dean have actually had several dog-related cases, but the canine-related antics are at their worst in ''All Dogs Go to Heaven.'' The episode will make any dog lover just a bit wary of adopting a new pet for fear that it might be a murderous skinwalker (if they believe in that sort of thing, of course). And Sam admitting he has changed—a.k.a. lost his soul—is just a sad cap to a strange episode. —Jonathon Dornbush
7 of 10
4. ''Out With the Old''
Season 7, episode 16
The two main plots in this episode featured Frank trying to figure out Dick Roman's plans and the Winchester brothers dealing with a handful of cursed objects, including a pair of ballet slippers that make people dance themselves to death. Dick Roman? No thanks. Cursed slippers? Again, no thanks. —Samantha Highfill
8 of 10
3. ''Clap Your Hands If You Believe''
Season 6, episode 9
Dean is abducted by aliens that turn out to be fairies. Also, there are elves?and a leprechaun. Like, what? —Samantha Highfill
9 of 10
Season 1, episode 2
After a relatively strong pilot, the show took a turn for the worse with its first monster (no demons or spirits this time!). Every supernatural show these days needs to include a wendigo episode it seems, but the Winchesters' battle with the monster is a rough second step for a show in its infancy. Even creator Eric Kripke admitted in a series retrospective the episode is one of their worst, and with a disappointing wendigo design to top it all off, the episode was a poor indication of the much stronger work that would come. —Jonathon Dornbush
10 of 10
Season 1, episode 8
Even the show's writers know how bad ''Bugs'' is—they mocked the episode in season 4's ''The Monster at the End of This Book.'' Cliché-riddled (a Native American curse is behind the bugs) and replete with gross visuals, ''Bugs'' clearly indicates a show still trying to figure out its tone and style. Early episodes of Supernatural pulled from the vast wealth of horror shows and films to come before it, but in ''Bugs'' they forgot to make things scary and just left a disgusting hour for fans to watch.—Jonathon Dornbush
How do the rest of Supernatural's episodes stack up? See:
Supernatural: 40 Best Episodes
Supernatural complete episode ranking: No. 41 to 189