Kevin races home and prepares for the burglars, crafting an elaborate series of booby traps. He maps it all out: there are toy cars to slip on, ice on the steps, a flaming hot doorknob, a nail on one of the stairs, a fan ready to coat a burglar in feathers, and more.
It's like a game of Mousetrap—just life-size, and capable of killing you.
Kevin says grace and is about to eat a microwaveable macaroni and cheese dinner—but the clock strikes nine and the burglars arrive.
Kevin pumps his BB gun and waits.
Harry and Marv knock on the door, claiming they're Santa and an elf. Through the dog door, Kevin shoots Harry in the crotch. He reacts in pain (obviously).
Kevin is ruthless, and no one to mess with.
Marv puts his head through the dog door, and Kevin shoots him between the eyes.
The burglars decide to split paths: Marv goes down to the basement, while Harry goes around the front.
Harry immediately slips and falls on the icy steps, while Marv does the same around back, crashing to the bottom of the stairs leading to the basement entrance.
Cue a sarcastic slow-clap.
Harry tries to mount the stairs, falling a second time, while Marv struggles to even get up. Using a crowbar, Marv tries to open the door—before realizing that it's (ominously) unlocked.
He enters the basement and tries to turn on a light—but the light cord is actually attached to a clothes iron, which flies down the laundry chute and smashes him on the head.
Harry forces his way to the top of the steps—and then burns his hand on the hot doorknob.
Climbing up the stairs inside the basement, Marv loses his shoes on the sticky tar that's Kevin's spread on the stairway. Then he steps with his bare foot on a nail and falls back down the stairs.
Harry heads back to the kitchen entrance and opens the door—it's unlocked, but tied to a blowtorch, which burns the top of his head. He charges back in, tearing off the blowtorch.
Harry exits the basement and goes back outside, where he decides to climb in through a window.
Meanwhile, Harry runs through a booby trap that coats him in glue and then covers him in feathers blown at him by a fan.
After Marv enters the window, still without his shoes, he hurts his feet by stepping on Christmas ornaments Kevin spread under the window.
Heading towards the upstairs staircase, the two burglars meet up and then promptly slip on toy cars. When they get up, Kevin smacks them with paint cans tied to string, knocking them over. Harry loses his gold tooth.