Ed, Edd n Eddy's Boo Haw Haw is the half-hour Halloween special of Ed, Edd n Eddy. In this episode, the Eds attempt to find the town of "Spook-E-Ville" on Halloween by using a dated map courtesy of Eddy's Brother. However, along the way, Ed has hallucinations of the kids being horrific monsters due to watching so many monster movies on TV earlier in the beginning.
Edd is organizing leaves on the school steps when Eddy bursts through the doors, complaining about the after-school detention that he got on Halloween, though Edd points out that he put processed cheese in a teacher's desk. Eddy quickly shakes this off, however, and leads Edd off to Ed's place, promising that he has something that will make this the coolest Halloween ever. When they get there, they find Ed inside, surrounded by many, many boxes of VHS tapes. Each tape is of a horror movie, and it seems that Ed has pretty much spent the whole month in his room, watching horror movies. Worse, he doesn't really seem to be paying attention to the world, as he's become a zombie to his TV. Edd has a solution, however: unplug the TV, and Ed will wake up. He proceeds to do so.
Once the TV shuts off, Ed's eyes fizzle static. Soon enough, though, they return to normal, and he looks around his room. Fully lucid, he loudly declares that it's Halloween, the night when ghosts and goblins come out to play. Eddy agrees with his friend's assessment, and then goes on to say he has something that'll make the night even better: a map his brother gave him that leads to a neighborhood where they give out buckets of candy, the one and only Spook-E-Ville. Edd, uncertain about the veracity of this map, asks to examine it, and after looking it over declares that despite the horrible penmanship, it's almost certainly a fraud, like a certain other map. Ed is made unhappy by this announcement, and Eddy milks this unhappiness for all it's worth, forcing Edd to give in against his better judgement to keep from ruining Ed's Halloween.
When the night finally comes, the Eds are all costumed up. Eddy is going as a zombie version of Elvis, Ed is wearing the costume of Lothar, a Viking who somehow rules Montezuma, and Edd is dressed as the Bubonic Plague. After some minor bickering, the Eds head out to start the search for Spook-E-Ville. Ed is distracted, however, when he hears strange voices, and he creeps over to the alley where the voices are coming from to listen in. Inside the alley are the Kankers, having a cookout. Ed's eyes fizzle static, and he sees something entirely different: three witches tending a cauldron. As he looks on, horrified, the witches cast a spell on the night, cursing their foes to suffer from many enemies that shall rise from the underworld and get in their way. As Ed runs away, terrified, the Kankers merely look at each other, wondering what the ruckus they heard was, with May reminding them that roasted marshmallows make her fart.
Meanwhile, Edd is scouring the map to try and find out what the first clue is. As near as he can discern, it's a dented stop sign. Suddenly, Ed runs up and grabs them, warning about the curse. Eddy jokingly says that it falls on Ed to protect them, and Lothar agrees. Edd and Eddy are starting to refocus on the map when Ed shoves them into a shed and warns them of something evil. The evil thing in question is Jimmy, who is dressed in an alien costume. This isn't what Ed sees, however; Ed instead hallucinates that Jimmy is an actual alien. After shouting at Jimmy that Earth isn't his salad bar, Ed runs up and slams a stop sign on him repeatedly, beating Jimmy into the sidewalk. Eddy laughs at this show of comedic violence while Edd looks on, horrified. Ed then heads over to his friends, and Eddy congratulates him on his protection. Behind them, Sarah comes over to her downed friend and learns that Ed inflicted violence on him.
Edd is scared, as Ed has broken the rules of so-called Halloween etiquette. He doesn't have much time to worry about this, however, as Sarah arrives and angrily wants to know what they meant by hurting Jimmy. Once again, Ed hallucinates, and he sees Sarah as a vampiress who must be vanquished. After a short tussle, Lothar emerges victorious, burying Sarah in the ground. Eddy, having noticed that they've found a dented stop sign in the form of the weapon Ed used on Jimmy, leads them onward, with Edd growing ever more concerned about the sanity of his friend.
While trying to catch up with his friends, however, Edd runs into a Medusa. This Medusa is probably the most improbable costume for the actual person in it, however, who pulls him along gleefully so they can trick-or-treat together. Eddy notices, and asks Ed what Edd is doing trick-or-treating with Nazz. Ed, as usual, hallucinates and attacks, actually seeing Nazz as Medusa. After a brief battle, Lothar emerges victorious once again, having encased "Medusa" in cement as a sort of poetic justice.
Ed then grabs a wagon and stuffs his friends into it. They take off and move around fast. However, all rides must end, and this one ends with them crashing into a rusting hearse parked in someone's backyard. By now, Edd is seriously worried about his friend Ed, but Eddy ignores Edd's fears, instead instructing him to read the next clue. Edd reads it, and learns that they're supposed to find an abandoned hearse–which they just did. Edd is suddenly distracted, though, as an egg hits him in the face. The perpetrator is none other than Kevin, who has decided to spend the night pranking people with eggs. The next victim of his is Eddy, leaving only Ed to face the music. An egg slams into his face, and Ed declares a retreat, throwing his friends over the cliff before facing down this newest villain, whom in his mind's eye appears as a headless horseman, throwing flaming pumpkins at him. The next pumpkin that comes at Lothar is sent back towards the horseman, knocking him off his "horse". Ed grabs the bike and flings it back towards Kevin, where it falls apart. Ed then leaps off the cliff, declaring that the witches' curse shall be for naught, and lands on his friends. Edd once again brings up Ed's need for a psychiatric evaluation, but Eddy ignores him, once again placing the trip to Spook-E-Ville at the top of the list in importance. He then orders Edd to read the next clue, which says that at the bottom of an embankment they will find a large oak tree. Unfortunately, there are hundreds if not thousands of trees before them, but Lothar has a "magic spatula" that he says will lead them to the correct tree. Ed then leads his friends to the forest until he stops, hallucinating again. This hallucination is of a spider, grotesque but friendly, descending a tree. This spider is really Jonny in a spider costume. Ed makes an offering of Jimmy's candy, which he had stolen, and Jonny accepts it, telling the Eds that they should head down a path that he points to and calling after them that, if they see Plank, they should tell him to get over to his best friend.
The Eds spend a long time on the path, but when they start to fear they're getting nowhere, they find Rolf, celebrating another one of his archaic rituals. Ed, of course, hallucinates and attacks, sending his spatula into Rolf's eyes and blinding him. He then grabs his friends and hustles them along the path only to come upon Franken-Plank, whom he beats up with a stick. Edd is once again worried by this, but fed up by what he thinks of as needless hassle in reference to Ed, Eddy simply grabs the map and walks on, declaring that he's going to Spook-E-Ville.
When Eddy can't read the map, however, Ed steps in once again, reading it. He declares that they have to find a big rock just as he walks into it. They then have to touch a shovel, which is magically just behind the rock, go under a hose, one of which is also only a few feet from the shovel, and then close their eyes and take ten steps backwards. Eddy performs all of these steps perfectly before he turns around and smiles widely, glad to have finally reached the promised land of Spook-E-Ville.
While Eddy looks around Spook-E-Ville with joy in his eyes, Edd looks at it with a more jaundiced eye, seeing a strange familiarity in its layout. Ed, still hallucinating, senses that the monsters they defeated before have all banded together, and he runs off, chanting about digging holes. Eddy, meanwhile, marches up to the first house he sees and rings the doorbell. Then rings it again. And again. And again. Never receiving a reply, Edd decides that his suspicions are confirmed, and tries to tell Eddy; when minor hints don't get through, Edd finally outright states that the map led them in a complete circle back to the cul-de-sac.
Before Eddy can fully consider the implications of this, Ed runs up and grabs his friends. The trio then see the kids, angry and advancing on them, seeking revenge for the indignities visited upon their persons (or in Jonny's case, Plank's body). Ed quickly runs to a backyard and throws his friends down in a hole. He leaps in after them and pulls part of a fence over them before hanging up his costume and declaring that Lothar is pooped. Ed sits down in a chair made of dirt in order to relax. Eddy starts to angrily complain about not getting to trick-or-treat, but bigger problems arise when the fence is lifted off the shelter and tossed away by the kids, who descend upon them. Eddy calls for Lothar to help them once more only to hear that there are no such thing as monsters, as the curse has been defeated. While the kids beat up Edd and Eddy, Ed merely reads a newspaper, only pausing to glance up once. When he does, he hallucinates again, but he does not see violence and horror. Instead, he sees his friends happily rolling around as flowers rain down upon them, and with a chuckle he returns to his newspaper, cheered by the sweetness of Halloween.
Edd: [to Eddy, as they both stand at the doorstep of a certain house] "Um, Eddy?" Eddy: "What's with these people?" Edd: "Eddy, look, do you notice anything familiar about this house?" Eddy: [peeking in through the mail-slot] "I bet ya they're fakin' not being home!" Edd: "Oh for heaven's sakes, Eddy – this is your house!" Eddy: [pauses] "What? I win the lottery or something?"
Eddy: "Hey, blowhard! You dented my hair!" Edd: "I think I bruised my coccyx!" Ed: "No thanks are necessary!"
Eddy: "It's Spook-E-Ville or bust – got it, Spore-Boy? Next clue?" Edd: [to himself] "'Spore-Boy'. Witty. Very witty."
Rolf: "Dodo Ed-boy, tell Rolf why Rolf shouldn't beat you mercilessly with a stick?"
Ed: [about to smash Jimmy with a stop sign] "Earth is not your salad bar!"
Ed: "You shall not feast upon our lives this eve, Vampiressessessess!"
Ed: "Lothar no need no stinkin' map, Eddy!" Eddy: "Yeah. That's because Lothar needs a stinkin' brain!"
Eddy: [to Double D]: "Ed this, Ed that, why don't you just marry the guy? I'm going to Spook-E-Ville! Ed: "I'm already taken, Eddy."
Eddy: [angrily kicks school door open, hitting Edd, and exits] "Stupid teacher! Can you believe the nerve of this guy? Dishing out detentions on Halloween! Edd: "Reap what you sow, Eddy. You filled the teacher's desk with processed cheese. A strict violation of school code." Eddy: "Hence the violation! I got somethin' that'll make this the coolest Halloween ever!"
Lee: [to her sisters around a campfire] "So I tell him, what size boot your face wear?"
When Ed says "Kids these days" near the end of the special, his feet have four toes, despite the fact he has been seen with three toes before (also, most characters have three toes on their feet, not four).
During the fight sequence at the end of the episode, if you pause it on Edd and Eddy, you can see three Edds and two Eddys.
If you look closely at the pile of movies in Ed's room, a white covered tape with a butcher knife is seen called "Danny the Butcher" as a reference to Danny's Lupo the Butcher. This is also another reference to Danny Antonucci's alias "Lupo D. Butcher."
When Rolf was harvesting the mushrooms, they were growing out of the ground. Normally, edible mushrooms grow underground.
The three video tapes that Edd picked up in Ed's room were "Medusa's Hair Salon", "The Headless Horseman", and "Curse of the Witches". These tapes represent the things Ed saw in Nazz, Kevin, and the Kankers, respectively.
When Ed is dragging Edd and Eddy into the forest after beating up Rolf, he says to run away before the troll's mother shows up. This is a reference to the monster Grendel and his evil mother in the epic Beowulf.
The headstone in front of Eddy's house says "Here Lies Captain Ahab." This is a reference to Moby Dick.
This special is the second episode based around a malicious misleading treasure map that was drawn by Eddy's Brother. The first episode was "O-Ed Eleven."