(Video opens with a shaky, first-person perspective. The view is of a vast, cratered, orange landscape under a dim light. A slice of pepperoni pizza.)

V.O. (Voiceover, a tiny, cocky, male voice): "Mission log: Barry the Bacterium. They said the 'five-second rule' was a myth. A scare tactic. Well, I've been on this floor for at least seven. Time to prove the naysayers wrong. Initiating infiltration."

(A giant, fleshy cavern—a human mouth—descends from the 'sky'. The camera is lifted up. Epic, 80s action movie synthpop music kicks in.)

V.O.: "We're in! The jaw-gates are closing! No turning back now!"

(The world plunges into darkness, then is illuminated by a flashlight beam attached to Barry's 'head'. He is on a soft, pink surface. Suddenly, the surface beneath him moves.)

V.O.: "Whoa! Tectonic activity! It's The Tongue!"

(The camera whips around as Barry is tossed and tumbled. He narrowly dodges giant, white pillars—the teeth.)

V.O.: "Evasive maneuvers! Dodge the Enamel Towers! Duck the Molars of Madness!"

(With a mighty heave, Barry is flung backward into a dark tunnel—the esophagus. It becomes a high-speed waterslide.)

V.O.: "YEEEEEE-HAAAAAW! Riding the Peristalsis Parkway!"

(The screen shows a video-game style map of a human torso, with a blinking dot labeled 'BARRY' plummeting down the esophagus.)

V.O.: "Next stop: The Stomach. I hear the locals are a little... acidic."

(Barry splashes down into a churning, bubbling green sea—the stomach acid. Bits of half-digested food float by like wreckage. The music becomes more intense, like a boss battle.)

V.O.: "Whoa! Holy hydrolysis! This place has zero stars on YellowP! Gotta find a way out before I become a nutrient!"

(Barry uses a flagellum like a propeller, weaving between bubbling geysers and dissolving chunks of hot dog. He spots a small opening—the pyloric sphincter.)

V.O.: "There's my exit! Full throttle!"

(He zips through the opening and enters the winding, dark tunnels of the small intestine. It's like a high-speed chase through a canyon.)

V.O.: "Now this is more like it. Scenic route."

(Suddenly, a massive, white, blob-like creature drifts into view, its pseudopods reaching out. A WHITE BLOOD CELL.)

V.O.: "CODE WHITE! It's the Immune System Police! You'll never take me alive, you amorphous goon!"

(A frantic chase ensues. Barry barrels down the intestinal tract, doing loop-de-loops around villi. He finds a tear in the intestinal wall.)

V.O.: "Time to get off-road!"

(He squeezes through the wall and bursts into a rushing, red river—THE BLOODSTREAM. The music swells triumphantly. Red blood cells drift by like giant, inflatable rafts.)

V.O.: "I've hit the Red River Expressway! Unbelievable traffic, but the views are to die for!"

(Barry hops onto a red blood cell and surfs it. The camera zooms past different organs, shown as glowing, abstract cities in the distance.)
(He's pulled into a massive, pulsing cavern—THE HEART.)

V.O.: "Whoa... This place has a BEAT!"

(The camera shakes violently with each THUMP-THUMP of the heart, synced to a heavy drum beat in the music. Barry and his red blood cell raft are launched out of a valve at high speed.)
(The journey continues, a montage of sights: the spongy, windy passages of the LUNGS, the intricate filtering system of the KIDNEYS.)

V.O.: "World tour, baby! And I didn't even pay for a ticket!"

(Finally, he arrives in a vast network of flashing, sparking cables—THE BRAIN.)

V.O.: "The Command Center. The Big Brain. I wonder what happens if I just... touch... this one..."

(Barry reaches out a cilium and pokes a neuron. It sends a massive spark down the line.)

V.O.: "Uh oh."

(Cut to the outside world. A man sitting at a desk suddenly feels a tickle in his nose.)

Man: "Huh?"

(Back to Barry's perspective. An incredible, hurricane-force wind begins to pull him backward.)

V.O.: "MAYDAY! MAYDAY! INITIATING UNPLANNED RAPID EGRESS! I REGRET NOTHING!"

(Barry is pulled at incredible speed back through the body, a chaotic reverse-montage of his entire journey. He shoots up the trachea and into the nasal cavity.)

V.O.: "IT'S BEEN A SLICE! LITERALLY!"

(The screen becomes a hurricane of mucus and air. With a sound that builds to a deafening crescendo...)

Man: "AAAAAAHHHHH-CHOOOOOOOOOO!"

(Barry's camera perspective is launched out of a nostril, flying through the air in a perfect arc. The action music cuts out, replaced by gentle, slow-motion piano music. He sees the world—the office, the desk, the man—in stunning clarity.)

V.O. (in slow motion): "So long... sweet ride..."

(He lands with a tiny splat in a cup of coffee on the desk. The camera bobs on the surface. He looks up.)

V.O.: "Round two?"

(Final shot: The man picks up the coffee cup and is about to take a sip. Freeze frame. Roll credits with 80s synthpop music blaring.)