The episode begins with Little Bill covering his eyes and trying to tell Brenda the sounds of the vehicles that pass by. A garbage truck passes by the house and Little Bill guesses correctly that a garbage truck passed by. Brenda is amazed he got it right and tells him to guess the next one. Little Bill says that it's a motorcycle and a motorcycle does pass by. Brenda notes that Little Bill is really good at this game, but doesn't know if he can guess the next thing that passes by. A car pulls up next to the house and Little Bill thinks that it's the family car. Sure enough, Little Bill got that one right as well. Little Bill is very glad he got it right and tells Elephant that that means Bobby and Big Bill are home. They run to the door to greet them. Little Bill says hello to Big Bill. Big Bill says hello to Little Bill and tosses Bobby the keys to the car. Big Bill asks Bobby to put them in the cup on the table. Bobby catches the keys when Big Bill catches them and Bobby brags about his amazing catch. Bobby says that he is going to throw the keys into the plate. He throws them and the keys land in the cup perfectly. Bobby says that he makes the throw and the Blue Sox have won the game. He notes he just got back from his baseball game and his team won. Little Bill cheers for Bobby and asks him if he wants to play catch in the backyard. Bobby says that he'll play with him later and tells him that right now he has to practice "Old MacDonald Had a Farm" on his violin.
Little Bill says he knows that song and starts to sing the song. After Bobby leaves, Little Bill picks up the car keys from the cup and decides that he's going to try and throw them in like Bobby did earlier. Suddenly, the doorbell rings and Little Bill calls for Brenda and tells her someone is at the door. Brenda says she'll be right there and asks Little Bill to ask who it is. Little Bill asks who it is and the voices on the other end state that it's Andrew and his mother. Little Bill calls out to Brenda and tells him that it's Andrew and his mother, but Brenda is right next to him. Brenda laughs and says that she's aware of that. Brenda greets Mrs. Mulligan and Andrew says hello to Little Bill. Andrew asks Little Bill if he wants to come outside to play. Little Bill asks Brenda if he can. Brenda says if he puts Elephant back in his cage he can go out and play. Little Bill tells Andrew to come upstairs and find toys to take outside. When Little Bill walks up to his room, he still has the car keys in his hands.
Little Bill and Andrew arrive in Little Bill's room. Little Bill asks Andrew what he wants to take outside with him. Andrew says he doesn't know. Little Bill tells him to look in the toy chest while he puts Elephant away. Little Bill tells Elephant that he's sorry he can't come outside with him, but notes that Elephant can drink his water or sleep until he gets back. Andrew asks Little Bill if they can take his toy car outside. Little Bill says no and notes they always lose them. Andrew admits he's right. Little Bill asks if they can take the rocket outside. Little Bill says yes and adds that's a better choice. Little Bill promises Elephant that he will give him a nice treat when he gets back from playing with Andrew. Andrew notes they can also bring his fire truck. Little Bill says that's a good idea and puts the keys down on his bed without knowing it. The keys fall off of his bed and land on the floor. Little Bill says he'll find something to play with. He says that he'll race Captain Brainstorm's ship against the fire truck. Andrew notes that a fire truck could never beat a spaceship. Little Bill says that Andrew's fire truck has hyper blasters that makes it move faster. Andrew thinks that's cool. They both race their vehicles from Little Bill's room. While they run, Little Bill accidentally kicks the car keys underneath his bed.
Little Bill and Andrew run out into the hallway. Andrew tells Little Bill that he has changed his mind and says that he's going to back and get the rocket. When Andrew leaves, Little Bill listens to a conversation that is taking place downstairs. Big Bill asks Bobby if he's absolutely sure that he put the keys in the cup. Bobby insists that he did. He tells Big Bill that he threw the keys to him. Bobby says that after he caught them he threw them into the cup. Big Bill wonders who took them out. Bobby says he doesn't know, but insists that he knows they were in there. Little Bill knows that he had the keys after Bobby put them in the cup, but he doesn't say anything. Big Bill says that Bobby needs to find them soon because otherwise they will be late for his violin lesson. Bobby tells Big Bill he'll find them. He's very upset that Big Bill doesn't believe him. Little Bill realizes that he needs to find the keys and he runs back upstairs. Andrew says that he's ready for their spaceships to take off. Little Bill tells Andrew that he can't go outside right now. Andrew asks why. Little Bill says that he just can't and doesn't tell Andrew the truth. Andrew is very disappointed and asks if he can take the rocket outside.
Little Bill says that he can. Andrew runs downstairs and tells his mother they can go outside now because Little Bill isn't coming. Little Bill runs back into his room and starts to look for the car keys. He calls out for the car keys and looks in his closet. They aren't there. He tells Elephant that he can't find the car keys. He tells Elephant that if he doesn't find them Bobby will be late for his violin lesson. Little Bill wishes he had the car keys and imagines that the car keys fall into his hand. He is glad that the wish worked and then asks for an ice cream sundae. That also comes true and Little Bill then wishes for a coconut. Little Bill then says he wishes he had a baby elephant and one appears in his imagination. Little Bill is snapped out of his imagination when Bobby comes in the room. He asks Little Bill if he's seen the car keys. Little Bill doesn't answer and Bobby asks him again. Little Bill mutters to Bobby that the car keys might be in his room. Bobby asks Little Bill to repeat what he said. Little Bill says that they are probably in here. Bobby asks Little Bill why they would be in his room. Little Bill puts his head down and says that he took them out of the cup. Bobby asks what happened to them after that. Little Bill says that they got lost. Bobby is very upset at Little Bill for losing the car keys. Little Bill insists that it isn't his fault and says that he was playing baseball with them. He says he was only being like Bobby. Bobby is very upset he is going to miss his lesson. Little Bill says he's really sorry. Bobby says it's okay because now they're going to find the missing car keys. Little Bill isn't so sure, but Bobby says that they'll do it together. Little Bill feels better. Bobby says that they are going to play detective.
Bobby tells Little Bill to retrace his steps and remember what he did in here before the keys went missing. Bobby asks Little Bill why he came to his room after he took the keys. Little Bill says that he was getting some toys so he could go outside and play. Bobby notes that the keys might be in the toy box. Little Bill says that they should look in the toy box. Big Bill calls into the room and asks Bobby if he found the keys yet. Bobby says that he's still looking. Little Bill tells Bobby that they're not in the toy box. Bobby asks him what he did after going to the toy box. Little Bill says that he put Elephant back in his cage. Bobby tells Little Bill to show him exactly how he did that. Little Bill says that he put Elephant's ball on the bed and then reached in and took him out. He realizes that the ball fell off of his bed and says that the keys may be under the bed. Bobby tells him to look under it and Little Bill does.
Sure enough, the keys are under the bed. Bobby tells Little Bill he did a good job remembering everything. Little Bill is glad they did it. Big Bill calls up to Bobby and Little Bill and tells Bobby that they have to go. Bobby and Little Bill run downstairs and Bobby tells Big Bill that they found the car keys. Big Bill is happy and asks where he found them. Little Bill says that they were in his room and admits that he took them out of the cup. Big Bill tells Little Bill that he knows better than to take the keys out of the cup. He reminds him that they're not toys. Little Bill says he knows and he's sorry. Bobby tells Big Bill that Little Bill helped him find the keys. Big Bill is glad that they were found and tells Bobby that they need to go. Big Bill notes that they have the keys, violin, and violin player so they're ready to go. Bobby asks Little Bill if he wants to ride along. Little Bill says yes and asks if he can help Bobby at his violin lesson. Bobby asks him how he's going to do that. Little Bill says that when Bobby plays "Old MacDonald had a Farm" he can sing. Bobby says that he thinks that would help a lot. The three guys get into the car and the episode ends with all of them singing "Old MacDonald had a farm".