"It's a gooey intergalactic mission when the Mexican mariachi band Los Galacticos accidentally blasts off into space to save the Earth from gooey aliens Uniqua and Austin."
Pablo, Tyrone, and Tasha are in the backyard wearing black and white sombreros and holding instruments. They introduce themselves as the members of the world-famous band Los Galacticos. They sing "Los Galacticos". Tyrone explains how they are recieving a new tour bus. The backyard transforms into a mostly-empty parking lot. The band thinks they have spotted their new tour bus and get inside the "bus". Pablo tells the others that it does not look like a normal tour bus. He presses a button, and appears outside of the "bus". They hit the button again, bringing him back inside the bus.
Tyrone activates the vehicle. It flies off, revealing their real tour bus behind it. The band notices that they are flying and realize that they are not in a tour bus. They are in a spaceship. The ship pilots them into outerspace. The three band members are petrified.
Meanwhile, two Googor aliens, Gooniqua and Goostin, are searching space for objects to cover in goo. They sing "We Love Goo" as they explain how they love "gooing" things. They spot Pablo, Tyrone and Tasha in the spaceship, flying toward them, and think that perhaps they are trying to stop them. They make a contact with the band, demanding to know who they are. The band tells the Googors they are from Earth. The Googors gasp, warn the band not to get any closer, otherwise they'll be gooed. The band is scared, but in an attempt to turn the ship away - they head in the direction of the Googors. The Googors respond by covering the spaceship windshield with goo. Gooniqua and Goostin taunt the band, telling them that now they are going to goo their planet Earth.
The band is confused. Pablo lowers his head in despair, and by chance - presses the switch that activates the windshield wipers. The goo is wiped off, but... the band is horrified to see that they are heading for the sun! Luckily, Tyrone presses the right button that makes the ship stop and turn around. Tyrone tells the others that if they are going to save Earth, they must learn to control the spaceship and stop the Googors. They sing "Pushing Every Button" as they find out what every button and control in the ship does. The aliens see the ship spinning around and think the band is retreating. They laugh and goo a meteor.
The three band members are satisfied after they have learned what every button does. They tell the Googors to "bring it on". The Googors try to goo them, but Tyrone dodges every shot. After shooting a 'goo pie' at the band members, Goostin and Gooniqua prepare a giant goo bubble to be launched toward planet Earth. After shaking the goo off their spaceship, Tyrone accelerates the ship's speed and commands the band to turn the ship, after passing the goo bubble. Pablo activates the shield, and the goo bubble rebounds off the spaceship, and heads straight toward the Googors' ship. It splats on the ship, making it spin out of control. Goostin and Gooniqua scream. Before their ship crashes into a nearby moon, Tyrone teleports them out of their ship and into theirs.
The Googors thank Los Galacticos and are brought to Earth. The five sing "Earth Es Muy Bueno" as they describe how wonderful Earth is. Tyrone compliments the Googors' singing, and offers them to join their Mariachi band. Goostin and Gooniqua accept. Goostin then notices the real Los Galacticos tour bus and asks about it. "Wait a minute... If this is your bus, whose is that?" The band members suddenly realize that they boarded the wrong bus. Three female aliens appear and ask Los Galacticos for their autograph. They see the ship that the band piloted and enter it. They wave goodbye and zip into space.
"This has been a strange day" said Pablo and his stomach starts to growl. Tyrone invites everybody to his house for chips and salsa. The characters sing the end song and run into Tyrone's house for a snack. Pablo, Tyrone, and Tasha open the previously closed door and shout, "Los Galacticos!"