Level 3 is the third level of The Simpsons: Hit and Run. This is Lisa's level for the game and takes place in the coastal side of Springfield called Squidport, The main plot of Lisa's adventures in the coastal region are to investigate the disappearance of Bart after he was abducted and last seen lurking in Squidport.
Lisa goes into The Android's Dungeon and asks Comic Book Guy where Bart is. Comic Book Guy is too busy to answer, as he needs a new comic book quickly. Lisa raced a nerd to the Squidport, where she took the comic. She drove back to Comic Book Guy, and gave him the comic. Unfortunately, he did not know where Bart was.
She makes another attempt to find Bart by going to a Krusty Burger. She finds Apu. He is mad that Cletus is bringing it roadkill. Lisa agrees to help Apu steal the roadkill from Cletus. She succeeds, but Apu doesn't know where Bart is either, but suggests she sees Professor Frink at the observatory. When they get there, Lisa asks him, but all Frink can say is that he remembered Bart helping him in the last level and then disappearing in a bright light. He doesn't know where Bart is though.
Lisa goes to the observatory to talk to Grandpa in hopes that he knows where Bart is. He is more concerned about the black sedans, so Lisa agrees to destroy them. First, she goes to pick up Otto's school bus. Then, right before she starts, she sees Bart's lucky red hat. She then goes to Aztec Theater and Squidport to destroy the remaining sedans.
Lisa goes to Chief Wiggum hoping he knows where Bart might be. She finds him at the Monty Burns Casino. She asks him where Bart is, but he is too busy. Wiggum is currently trying to bust Snake under the three strikes law, and Wiggum refuses to help until he finds evidence. However, due to the fact that he's "a very, very bad cop", he hasn't found any evidence against Snake yet. Lisa agrees to help get them. He then suggests that she go undercover, and mentions using Ralph's halloween costume.
Lisa will need to buy her cool clothes as a disguise. She then accompanies Chief Wiggum in collecting evidence. They find the first evidence pretty quickly, which is the fact that Snake bought Counterfeit Designer Jeans, which is the foulest of crimes. while nearing the dam, they find him running over an elderly citizen without a permit. They later collect litter that he threw out of the vehicle, thus gaining all the evidence they needed in regards to put Snake in jail. In return, Chief Wiggum mentions seeing some Government officials with Bart, indicating in his mind that they might have sent him on a cruise as deals are good currently.
The Sea Captain tells Lisa he saw Bart forced into a limo. Lisa destroys the limo. Bart had earlier escaped the limo and got on a ship. Lisa got to him and found that his brain wasn't working properly.