The episode begins with The Boy rocking out on a toy guitar performing the song School's Out and jumps of the bed and uses the guitar to knock some stuff off the desk. The Dad is heard from another room and tells The Boy to be quiet and go to bed and that he is talking on the phone.
The Boy then tells his father that he couldn't make that out and turns up the song louder,The Dad then comes in and turns off the song and tells The Boy that he doesn't "wanna hear a peep out" of him or he'll wish he was out for summer. Then The Boy tries to complain but his father says he doesn't wanna hear a word, Not a peep then leaves the room.
The Boy starts muttering himself and then picks up Destructo telling him that if he can't make noise no one gets to and he tells Destructo "Not A Peep Or Else." The Boy then throws Destructo against the wall and The Boy goes to bed. Destructo then wakes up saying that his programming is complete, he remembered what The Boy said to him "Not A Peep or Else" and he says he's got it.
Meanwhile under the bed, Mr. Bumpy is performing "Schools Out" at the Karaoke Cafe while all the other characters dance to the song. Just then Destructo comes in and tells everyone not to make a peep. The Cute Dolls see him and tell him they want him to join the dance party then Destructo tapes the Dolls mouths shut, then puts earmuffs on Yellow Bunny causing her to fall over, he then tells Squishington to put a sock in it as he shoves a sock in his mouth and ties up Molly Coddle.
Then Bumpy is turned around asks if everyone is having a good time not noticing Destructo and then tells everyone he can't hear them. Bumpy tries to asks again when he turns and sees everyone has been tied up and gagged and says he really can't hear them and tells them does he know how to party or what.
Just then Destructo gives Bumpy a tap and Bumpy turns around and sees him and asks if he wants to do karaoke, then Destructo tells Bumpy "Not a peep" especially from him. Destructo then rolls Bumpy up into a ball twisting his limbs and throws him down, Destructo then picks up a microphone and tells everyone "Not a peep" and rolls off.
Bumpy then says Destructo is a party pooper and he untwists himself and tells the other characters that it's lights out and it's time to conga. Then one of the Cute Dolls removes duct tape from her mouth and says that Destructo is to powerful and strong to mess with and one of the other Cute Dolls say she has to do her hair and other Dolls say they also have to same and leave.
Then Bumpy tells Molly to grab onto him and boogie and she says as much as she likes being tied up by Destructo she then says she has a whole day of comforting tomorrow and takes Yellow Bunny by the hand and leaves. Then Bumpy turns to Squishy and tells him that they don't need anyone else to have a good time, Squishy then says his bowl sitter leaves at eleven. Bumpy asks him does he have to go too, Squishy then says it would appear that way and him and all the other characters expect Bumpy leave because they don't want to deal with Destructo.
Bumpy then sees he's alone and says he doesn't need anyone else to party and that he can party himself, Bumpy then declares it's Bumpy time and puts on a party hat and starts beat-boxing while swinging a noise maker. Then he says it's not fun without anyone else and it kinda cuts down on the applause.
Then Destructo hears Bumpy's beat-boxing and Bumpy sees him and says "hello darkness my old friend". Destructo beats up Mr Bumpy and throws him down with a cork in his mouth. Destructo once again tells him "Not a Peep" and rolls off. Bumpy has had enough and says nobody tells him not to party and something's gotta be done about Destructo calling him "Rivet-Brain and he's the one to do it and turns to the viewers saying he'll do it quietly.
Later, Destructo is still searching around for rule breakers, he starts scanning around and spots Mr Bumpy. He keeps an eye on Bumpy and then turns around, Bumpy pulls out a whoopee cushion and squeezes it, making a loud flatulent sound. Destucto turns around and is about to say "Not a Peep" but Bumpy hides the whoopee cushion and Destructo is confused, seeing that Bumpy isn't making any noises.
Destructo turns around again, Bumpy pulls out the whoopee cushion and makes a noise again, Destructo is angered and turns around. Bumpy this time hides the whoopee cushion in his mouth, Destructo turns around again and Bumpy squeezes the whoopee cushion from inside his mouth.
Destructo then grabs Bumpy, twisting him into a ball, bouncing him like a basket ball and tosses him inside a bin. Destructo repeats "Not a Peep" and then leaves, Bumpy is heard from inside the bin and says "being quiet is tougher than it looks."
Later, Destructo is shown moving his arms and body in a robotic way, meanwhile Mr Bumpy is hiding and holding a long piece of string, he whispers to himself in delight that “this is going to be good.”
Bumpy sneaks up behind Destructo and ties the piece of string to him; Bumpy then disappears while Destructo beings to move. A loud rumble is heard, Destructo then pauses, he beings to moves, and the rumble is heard again.
Destructo angrily says “Not a Peep, or else,” not realizing that Bumpy tied a bunch of noisy objects to him, such as tin cans and spoons. Destructo then says, “My noise seeking fist missile will put a stop to this,” he then fires out his robotic fist, leaving a trail of smoke.
The fist missile then starts flying around the room, seeking the source of the noise, the missile then turns on Destructo and then starts chasing him. Destructo tries to escape, while the fist missile follows after him. Destructo jumps onto a chair and the string falls off him, he stands on top of the chair while the missile can no longer find the source of the noise.
Meanwhile, Bumpy is getting impatient and says, “Hey, what happened?” The missile then faces Bumpy and locks onto him. Bumpy’s pupils dilate and he covers his face, waiting to get hit. The hand then stops in mid air, Bumpy looks up and the hand shoots out aluminum foil over Bumpy, he then rolls away in a tin foil ball.
Later, Mr Bumpy is shown wearing white pillows on his feet, opening a box labeled "Silence Suit." Bumpy then takes out a puffy white padded vest. He puts on the vest and zips it up, covering his body and face while his eyes are sticking up. Bumpy then walks up to Destructo's home, "Fort Destructo" and quietly sneaks in.
Inside, Destructo is oiling up his neck with an oil can, Bumpy sneaks up behind Destructo and puts a pair of fluffy pink earmuffs on his head. The earmuffs are set on Destructo's ears and Bumpy quickly dashes away to take off the silence suit. Bumpy returns, this time pretending to be a one-man band, he starts making noises but Destructo can't hear a thing and begins to polish his armor. Mr Bumpy then starts banging on the drums and starts tooting a clown horn but Destucto remains oblivious to Mr Bumpy's actions.
Mr Bumpy then dashes off again and returns carrying a large black stereo speaker. Bumpy picks up the stereo and then buckles it to Destructo's waist. Bumpy then turns up the stereo's volume from 1 to 10, he then pulls out a black crayon and writes "11", and turns the volume up higher.
Bumpy then gently takes the earmuffs off Destructo's head, Bumpy then pulls out a metal pin, lifts it above his head and drops it. The pin hits the floor, next to a microphone lying on the ground and the sound is increased. Destructo hears the "ping" sound, turns to face Bumpy and says "Not a Peep", but his voice then begins to echo from the loud speakers.
Destructo then shouts out "Stop this at once" but his voice continues to echo loudly. He covers his mouth, and his eyes dart around, the stereo begins to screech and Destructo is disorientated by the noise. Destructo then bends down to pick up the microphone, but his wrist cracks and the noise is echoed through the speakers. Destructo becomes frustrated and his eyes become swirls.
Destructo growls in frustration and Bumpy returns to further Destructo's misery. Bumpy pulls out a feather, Destructo freaks out, his eyes pop out, the spring in his neck has sprung and he makes the "arooga" sound. Bumpy comes closer to Destructo while holding the feather, Destructo cries out "NO" and his voice bounces around again.
Bumpy then begins to tickle Destructo, he begins to chuckle uncontrollably and tries to cover his mouth to prevent himself from making noise. Bumpy continues tickling Destructo and he begins to sink lower and lower into the ground. The stereo speakers then burst and Destructo is revealed to be trapped in a hole in the floor.
Destructo is defeated, Bumpy then jumps onto the stereo and shouts out "PARTY TIME!", then everyone enters "Fort Destructo," including Molly Coddle, Squishington and the Cute Dolls. Squishington then gives Bumpy a party hat and the microphone, Bumpy is victorious and begins to sing "School's Out" again. Destructo is now woozy, he mutters "Not a Peep" but Bumpy then slaps on a piece of duct tape across Destructo's mouth and his neck spring pops out.
Meanwhile, The Boy is lying in bed and the Dad is heard talking loudly on the phone, the Dad continues yammering and the Boy then jumps out of bed. The Boy opens up the door, and calls out to the Dad, "Didn't you say Not a Peep?" The Boy then laughs and goes back to bed. Under the bed, Bumpy over hears the Boy and laughs out loud, Bumpy then proudly says "That's MY Boy" and smiles, ending the episode.
The Dad: (From the other room), Hey buddy be quiet in there and go to bed okay I'm on the phone.
The Boy: (Puts down to toy guitar) What!?, Sorry Dad couldn't make that out, (Turns up the boom box playing the song School's out louder).
The Dad: (Enters The Boy's room and turns off the song), Hey Pal I don't wanna hear a peep out of you or you'll wish you were out for Summer okay!
The Boy: Aww Dad!
The Dad: Uhh-uhh I don't want to hear a word okay, Not a peep, (Leaves the room).
Destructo: Not a peep!
Mr. Bumpy: Okay it's lights out you party mongers but now it's time to conga!
Mr. Bumpy: Hey Moll, grab on and boogie.
Molly Coddle: As much as I like being tied up by Destructo, I have a whole day of comforting tomorrow and.... (walks out holding Yellow Bunny's hand)
Mr. Bumpy: Come on Squish we don't need them to have a good time.
Squishington: Well my bowl sitter leaves at eleven and uhh...
Mr.Bumpy: "Et Tu", Squishington.
Squishington: Yep would appear that way, (walks out).
Mr. Bumpy: Hello darkness my only.. friend?
Mr. Bumpy: No one tells Mr Bumpy not to party! Something's gotta be done about that "Rivet-Brain," and I'm just the thing to do the some-ing!.. And don't worry.... I'll do it "quietly"...
The Boy: (calling out to The Dad) Didn't you say "Not a Peep?" (laughs and goes back to bed)
Mr. Bumpy: (laughing out loud) That's MY Boy!
- The Boy sings Alice Cooper's Schools Out, while Mr Bumpy sings parts of the song under the bed. Mr Bumpy also performs a full version of the song at the Karaoke Cafe.
- The Dad is voiced by Rob Paulsen, who is also the voice actor for Squishington. The Dad's voice sounds similar to "Yakko Warner" from Animaniacs, except his voice is less high pitch.
- At the Karaoke Cafe, various background characters are seen such as Yellow Bunny, Baby Snail, Little Robot (from Made in Japan) and Germ Girl (from Adventures in Microbia.)
- Mr Bumpy says "Et tu Squishington" which comes from the Latin phrase "Et tu, Brute", or "you, too, Brutus?" This was the last words of Emperor Julius Caesar before he was assassinated, signifying the utmost betrayal by an unexpected person, such as a friend.
- When Mr Bumpy says the line "Hello Darkness my only friend", this line is from the Simon and Garfunkel song "The Sound of Silence".
- Molly Coddle says the only line in this episode.