We First meet Rose Tyler as her alarm clock rings and sets her off on what she believes will be another routine day at her job at Hendrik's department store. However, this day will end much differently than she expects. At first everything seems to be going normally, but as the store is closing she is forced to stay and finish one bit of business in the basement of the store.

The basement, however, appears deserted. She stupidly proceeds to investigate a noise she hears coming from further into the basement. She gets even more nervous when her exit door slams shut behind her. To her astonishment, the mannequins littering the basement suddenly begin moving. She retreats as the figures begin approaching her threateningly. Finally, with her back pressed to the wall, she can retreat no further. It looks like she is done for as the mannequins raise their arms to deliver a blow.

Suddenly a hand grasps hers and an odd man tells her to run. They both run and make it to an elevator on the other side of the basement, but a mannequin manages to reach its arm in before the doors can shut completely. The strange man is forced to rip the arm right off in order to get the doors to shut. He tosses the now inert plastic to Rose.

Rose has no idea what is going on, but the only thing she can think is it must be some kind of prank. The Doctor introduces himself and quickly discounts her idea, before trundling her out a back door and telling her to scram before he detonates the device he is carrying in his hand. As Rose walks confusedly toward her apartment, Hendrik's blows up. Mannequin arm in hand, Rose runs the rest of the way home.

At home, Rose discovers that the explosion is the talk of the town. Her mom is eagerly spreading the word to everyone on the phone. Even her goofy boyfriend Mickey seems concerned about her near fatal experience, but actually he would much rather be down at the pub watching a match on the telly. Rose gives him permission to leave, but gives him the plastic arm to dispose of in a trash can along the way.

The next morning, Rose awakens to the realization that she has no job to get up for, but she is also still disturbed by last night's experience. She hears a noise at the door and finds the Doctor peaking through the cat door. He is apparently following a trail from one of the plastic creatures and it has led him to her door.

Rose drags the Doctor inside and begins trying to get answers to her questions. As she drones on, the Doctor explores her apartment. A noise from behind the couch attracts his attention, and as he checks it out, he finds the plastic arm that Mickey had thrown in the trash the night before. The arm is once again moving and indeed its hand manages to latch onto the Doctor's throat. As the Doctor struggles to pry the arm off, Rose assumes he is just joking around. At least she thinks that until the Doctor shakes the arm loose, and it latches itself onto her face. Using his sonic screwdriver, the Doctor is able to make the arm inert once again.

The Doctor tries to leave quickly, but Rose is not about to let him get away without an explanation. He tries to explain the concept of living plastic and the force that controls it, but it is all a bit much for Rose to believe. Despite being unsatisfied with his cryptic answers, the Doctor directs her to go back home. As she turns to leave, the Doctor returns to his TARDIS and vanishes.

Rather than going home, Rose turns up at Mickey's place to use his computer. She does a Google search for the Doctor and finds a website dedicated to the mystery man. With an address in hand, Rose persuades Mickey to drive her to the home of the man who created the website. She finds Clive, a real conspiracy nut, but he has some rather convincing evidence. He shows her many images of the Doctor taken from different periods through out time, yet the Doctor never seems to change.

Meanwhile, as Mickey waits in the car, he notices a nearby garbage can moving on its own. He gets out to investigate, but as he opens the lid, the plastic can sticks to him and sucks him inside itself. But when Rose returns from talking with Clive, she finds Mickey still sitting at the wheel, however, it's a very odd Mickey, one with a rather plasticky sheen.

The two of them proceed to a restaurant to get pizza, but Mickey seems single-mindedly interested in what Rose knows about the Doctor. He is so interested, that it takes him awhile to notice that is actually the Doctor who has been trying to serve them champaign. The Doctor pops the cork and it hits plastic Mickey in his malleable forehead. Mickey absorbs the cork into his head and spits it out his mouth.

All pretense of deception is over as the Auton-Mickey goes on a murderous rampage in an attempt to bludgeon the Doctor and Rose. The quick thinking Doctor does manage to grab Mickey's head and yank it off, but it doesn't stop the all out attack. The Doctor and Rose run for the back door with Mickey's headless body pursuing and wildly swinging club-like hands.

It just so happens that the Doctor has parked the TARDIS in the alley behind the restaurant, and with Mickey's head in hand, he enters the safety of the blue box. Rose can't figure out why he would want to get in a box when they are running for their lives, but she follows him in. To her surprise, she finds the TARDIS is bigger on the inside.

The Doctor gives her a brief rundown of the TARDIS before he tries to use Mickey's head to backtrack the signal that is animating it. However, before the TARDIS can get a complete lock on the signal, the head melts. They exit the TARDIS and Rose discovers they are in a completely different part of London.

Fearing the real Mickey might be dead, Rose tries to get more answers out of the Doctor. He isn't quite sure about Mickey, but he decides to let her in on his plan to use a vial of anti-platice to destroy the Nestene Consciousness, the entity that controls the Autons. Unfortunately, the TARDIS has lost the Nestene's signal. If only he could find its transmitter, something big and round. Rose subtly tries to point out to the Doctor that he is standing in front of the London Eye which couldn't get any bigger or rounder.

The two of them run to the ferris wheel and find an entrance to an underground passage. Sure enough, the find the Nestene Consciousness in a vat at the bottom of a pit, glowing like molten lava. All the Doctor has to do is toss in the anti-plastic, but he can't do it without giving the creature a chance to surrender. As the Doctor approaches the vat, Rose finds the real Mickey still being held alive. SHe tries to pull him toward the stairway back to the surface.

Meanwhile, the Nestene doesn't appear to be receptive to the Doctor's offer, but before the Time Lord can use his anti-plastic, two Autons step forward and grab him and his vial. The Nestene then proceeds to broadcast his signal through The Eye to every piece of plastic in London. The mannequins again come to life and begin terrorizing and murdering their way around the city.

With the Doctor being restrained by the Autons, Rose realizes it is up to her to do something. She bravely grabs a nearby hanging chain and uses it to swing down and knock the Auton holding the Doctor's vial of anti-plastic into the vat holding the Nestene Consciousness. As the concoction begins to work, the signal controlling the Autons terrorizing the city breaks down and the people of the city are saved. With the Doctor rescued, they grab Mickey and the three of them hop into the nearby TARDIS which the Autons have conveniently brought to them. They escape as the Nestene explodes.

With the danger over, the Doctor plans to take off. Before he goes, he does stop to make Rose an offer to travel through time and space with him. At first, however, she feels obligated to decline because of Mickey and her mom. With a shrug, the Doctor departs in his TARDIS, only to reappear a moment later. It seems the Doctor wants to give Rose one more chance. This time she can't refuse. With a kiss goodbye for Mickey, Rose runs for the TARDIS to join the Doctor on his adventures...