She thanks him and hands him a flyer, before going off to target more unsuspecting passersby. Marty and Jennifer, now rid of the collection lady, are about to kiss when a car pulls up and beeps its horn loudly. It's Jennifer's father, coming to pick her up. Jennifer hastily scribbles her number on the back of the clock tower flyer with "Love You!!!" next to that. She gets into the car. Marty looks at the back of the flyer. He smiles. Marty gets back on his skateboard and grabs a police car to tail behind. He makes his way back to his home neighborhood, Lyon Estates.
Marty lets go of another car and skims down this opening towards his house. As Marty rides up to his house, he passes a wrecked BMW sedan being pushed back into the driveway by a tow truck. Inside, Marty's father George McFly (Crispin Glover) is arguing with his supervisor Biff Tannen (Thomas F. Wilson). Biff is exasperated that George loaned him a car without telling him that it had a blind spot, leading him to have a head-on collision with another vehicle. George insists that he never knew the car had a blind spot.
He sees Marty and gives him a weak greeting, as Biff demands to know who is going to pay for his cleaning bill, seeing as he spilled beer all over his coattails. Biff then asks George if he's finished filling out Biff's reports. When George admits he hasn't done them yet, an annoyed Biff taps him several times on the head, reminding George that he needs time to retype them because he'll be fired if he hands in his reports in George's handwriting.
He expresses despair that all they've got in the fridge is lite beer, and helps himself to a beer before leaving. After Biff leaves, George hesitantly admits to Marty that he isn't good at confrontations. Marty asks about the car, which he had been planning to drive up to the lake with Jennifer. George apologizes.
The whole of the McFly family later sits down to dinner - George, his wife Lorraine (Lea Thompson), and their children Marty, Dave (Marc McClure) and Linda (Wendie Jo Sperber). Lorraine drops a thin cake onto the table. It says 'Welcome Home, Joey', next to a picture of a bird flying out of jail. Uncle 'Jailbird' Joey has failed to make parole, again. Linda chides that he's an embarrassment to the family. Lorraine reminds her that everyone makes mistakes in life.
Having enough of the conversation, Dave leaves for his job as a Burger King cashier, while Linda tells Marty that Jennifer called asking for him. This upsets Lorraine, who lectures Marty that 'any girl who calls a boy is just asking for trouble.' When Linda tries to defend Marty, Lorraine grows upset, insisting that when she was Linda's age she never 'chased a boy, or called a boy, or sat in a parked car with a boy.' Linda asks how she's supposed to meet anyone if she is to go through life like Lorraine did. Lorraine explains that it will happen just like she met George.
Linda rolls her eyes, as Lorraine once again relates the story of how they met: supposedly, George was up in a tree (just what he was doing, George has never explained), when he slipped, fell into the street and was hit by Lorraine's father's car. After taking him inside, and taking care of him, Lorraine felt sorry enough for George that she asked him to the Enchantment Under The Sea dance, which happened to be the same night the lightning bolt struck the clock tower. When they had their first kiss at the dance, she knew she was going to spend the rest of her life with him.
Sometime after midnight, Marty is awoken by a call from Doc, who asks Marty to stop by the lab and pick up his video camera that he forgot. Marty does so, and heads to the Twin Pines Mall. When he gets there, he finds Doc's van sitting in the parking lot, with his dog, Einstein, sitting nearby.
When Marty goes down to greet Einstein, the rear of the van opens up, and a heavily modified DeLorean DMC-12 sedan is backed down the ramp. The driver's door lifts up, and Doc emerges from the vehicle, greeting Marty, then instructs Marty to start recording. Doc places Einstein in the DeLorean and buckles him in, having Marty note the time on the watch around Einstein's collar, and in Doc's hand. Both are synchronized to the same time. Doc then closes the DeLorean's door, and pulls out a remote control, that he uses to maneuver the DeLorean around the parking lot.
When the vehicle is a specific distance away, Doc puts its brakes on, and starts ramping up its speed, before turning off the brakes, sending the DeLorean streaking right towards him and Marty. Suddenly, a bright light is seen from inside the DeLorean, as additional fire and lights are set off around it, and suddenly, upon hitting 88 miles per hour on the speedometer, the car vanishes in a puff of light and electricity, leaving a pair of fire trails behind from the red-hot tires. Doc excitedly cheers, but Marty is in shock, as it seems that Doc has just disintegrated Einstein.
Doc excitedly exclaims that he actually sent Einstein into the future... "one minute into the future, to be exact!" As if on cue, exactly one minute later, the DeLorean materializes where it disappeared, still traveling at the same speed as it was before, and screeches to a stop, now iced over. As Doc opens the door, Einstein is revealed to be alive and well, with his watch now one minute behind Doc's. Doc explains that Einstein likely believes that the trip was instantaneous. Doc shows Marty a device in the cabin called the "flux capacitor" which makes time travel possible.