Kevin heads to the kitchen and turns on the TV. He starts to wonder where everyone is, looking concerned.
Back on the plane, Kevin's Mom chats with his Dad.
Kevin wanders around the house, calling out to his different family members. He even heads down to the basement, where the creepy furnace freaks him out.
He runs outside and sees the cars are in the garage, and thinks his family didn't go to the airport (he doesn't realize they took a van).
Back inside, he thinks he made his family disappear—and he feels pleased.
Kevin celebrates: he hops on his parents' bed, eats junk food, and zooms around the house.
He breaks into his brother Buzz's secret stash, taking out firecrackers and chucking a copy of Playboy over his head (Kevin's not interested...yet.) Then, he uses his brother's BB Gun to shoot action figures down a laundry chute.
Soon Kevin will be exchanging those action figures for human targets—but in a justified way.
Next, he watches the movie his uncle wouldn't let him watch—Angels With Filthy Souls. But its violent death scene, in which one gangster shoots another, scares him. He covers his eyes.
On the plane, it's nighttime: Kevin's mother tells his father that she has a feeling they forgot something. His dad says he forgot to close the garage…but Kevin's mother says that's not it. Suddenly, she realizes, shouting, "Kevin!"
Back at the McCallister house, Kevin rides a toboggan down the stairs and directly out the door.
Cutting back to the plane, Kevin's mother consults with the airplane staff about trying to call home. She feels guilty.
It's just like losing your car keys in the couch cushion—except your car keys are your kid.