Doug's Garage Band is the second part of the twelfth episode of the third season of Nickelodeon's Doug.
Beebe gives Doug and Skeeter their first gig for their new band--but they have to let her join. Now, everytime Doug wants to add something to the show, he has to let in new members, and it seems they all just want to play the drums.
Doug, Porkchop, and Skeeter are pretending to play musical instruments while walking through town when they watch Chap Lipman on TV at the record shop. After listening to Chap Lipman talk about what inspired him to get into the music business, Doug and Skeeter decide to start their own band.
Doug's imagination: A female reporter is at the front of Doug's garage and shows the merchandise of Doug and Skeeter's band, showing the two dressed as rock stars. Skeeter, talking in an English accent, says that the band do all their composing inside the garage. Doug also ads that the band get their songs from anywhere, even writing a song about a plunger, impressing the reporter.
During the afternoon, the two begin recording their own music at the Funnie house. While Doug plays his banjo, he begins singing the song "Banging on a Trash Can." He and Skeeter talk about it at the Honker Burger and Beebe tells Doug that she can get her cousin to ask Jimmy Spackle, the guy at the record business, to listen to his tape.
Beebe later shows up at Doug's house later at night and gives him his tape, telling him that Spackle loved his song and set up his first gig for Doug to see him perform his song this weekend. She also tells Doug that she is now a member of Doug's band, telling him that he has to "think big."
Doug's imagination: Doug and Skeeter's song "Bangin' On a Trash Can", which is from the band's album Think Big from Jumbo Records, appears to have a music video, with a singing Beebe saying "Think Big" and with Skeeter drumming the top of a trash can drawn with red crayon. Doug also makes an appearance himself singing the lyrics to the song. Beebe is also shown dressed in black while hanging from an overhead chain crane shouting out "Think big". Doug makes another appearance, wearing a black suit as well, singing the lyrics to the song as everyone else says "Think big". As the music video continues, Doug, Skeeter, and Beebe are seen wearing over-sized white suits and continue singing "think big" as they perform on stage. When the song ends, the audience cheer for them.
As Doug is seen sleeping during the night, he wakes up and writes down more ideas in his notepad. So the next day, Doug goes to Connie's house and asks if she could make a big suit, only to find that Patti wants to play on the drums after she and Connie ask Doug if they can join his band. Doug suggests that his band can have two drummers and an audio harp player. He also get Elmo to do the light show by having him join the band, only to discover that he too plays the drums. When Doug asks Al and Moo for special effects, they tell him that they want to play on the guitars.
In Doug's garage, the rehearsal doesn't turn out as he has planned it and as the others play the instruments, they only end up playing dissonance. But after a few minutes of practicing, the instruments they play finally complement to each other, evoking harmony to the music. However, everyone argues about getting a solo for their instruments. So Doug tells them that they can all have a solo.
The next day, they perform their song at a kid's birthday party in the backyard of a house and the instruments they play start breaking. Doug then realizes that he is no longer having fun, and Jimmy Spackle, who was the same guy at the record shop, arrives and likes what he has heard. Beebe talks to Doug in private and tells him that he is officially banned from the band, telling him that Jimmy dislikes the banjo only because it's not rock 'n roll worthy. Doug (who is secretly glad to be out of the band) tells Beebe that the rest of the band is going to continue without him.
The next scene shows the Bluffington Yodel house where Jimmy asked the band to play in. But they were chased out since the people there, don't appreciate their music. The band at last was no more.
The final scene shows Doug and Skeeter using the trash cans as instruments as Doug states voice-over that he and Skeeter can wait a little longer to be famous, at least until Junior High.