This is the sixth level of the game where Bart is the playable character, set in the Springfield Squidport in the hours before the night ends.
 Going to the Lu
Bart talks to Apu about the aliens' plan, but he resigns, so he talks to Otto, who is taking the kids to Krustylu Studios for the tour, so they get into the School Bus and they collect the kids and take them there.
 Getting Down With the Clown
Bart then talks to Barney in a cadet uniform and finds out that Krusty is in the Springfield Squidport and Bart must get there before Krusty's Limo and he follows a Movie Truck to the Observatory and then he races the limo to the Springfield Squidport. Talk to Krusty to start the next mission.
 Lab Coat Caper
Bart then talks to Krusty and he follows Professor Frink to the observatory to find out more information about the alien invasion. Talk to him inside the observatory to start the next mission.
 Duff for Me, Duff for You
Bart talks to Professor Frink and finds out that the ray guns are in the Duff Trucks, so he goes to the brewery and hits the Duff Truck to collect the ray guns, then he returns to the brewery and gets a ray gun as a proof.
 Full Metal Jackass
Bart talks to Principal Skinner and he confiscates the ray gun, so he has to destroy his car and re-take the ray gun. Head over to Krustylu Studios for the next mission.
 Set to Kill
For this mission, you will need the Globex Super Villain Car, purchase it from Kearney at the Krustylu Studios entrance for 600 coins. Bart talks to Krusty and tells him to destroy the ray gun stands, and he does so, using the Globex Super Villain Car before returning to Krusty at Krustylu Studios and then Bart tells him that he destroyed the ray gun stands and Krusty saw the Aliens at the Duff Brewery.
 Kang and Kodos Strike Back
Bart tells Homer that the Aliens are at the brewery, and he says that it's Duff's worst disgrace since Duff Ice, so they use the 70's Sports Car and must get there before the Aliens escape in their Black Sedan. When they get there, Kang and Kodos tell Homer and Bart that Foolish Earthlings are raising their ratings as they've spread out even more cola through the water supply and it reached the Springfield Cemetery and the zombies will rise from the dead.
 Bonus Mission
 Milking the Pigs
Talk to Snake and he wants Bart to destroy Chief Wiggum's car and collect the evidence, and later a milk truck. He'll later reward you with his car, the Bandit.