The DeLorean time machine was Doctor Emmett Brown's most successful invention, a plutonium-powered time machine comprised of a DeLorean DMC-12 sports car that had to reach 88 miles per hour in order to time travel. On November 5, 1955, Doc slipped on his toilet while hanging a clock in his bathroom. When he came to, he had a vision of the flux capacitor in his head. It was constructed afterward and completed in 1985.
The first test
Doc Brown revealed his creation to his friend Marty McFly at Twin Pines Mall, in the early morning of October 26, 1985, and for its first test, Doc sent his dog Einstein one minute into the future. The sequence of events that followed were as so; after Doc revved up the engine to 65 mph while braked, he released the brake sending the car towards Doc and Marty. A faint glow developed at the front of the car and then engulfed the vehicle. The coils lit up, internal circuits glowed, and the flux capacitor fired rapidly. Suddenly the car seemed to explode just before it hit Doc and Marty. Fire trails then scorched the pavement where the vehicle would have passed through, completing the temporal displacement sequence.
For Einstein, the trip was instantaneous, but to Marty and Doc they had to wait exactly one minute to catch up to Einstein in the timeline. In the meantime, Marty asked why a DeLorean was used. Doc explained that it needed some style and implied that the stainless steel construction of the car helped it in temporal displacement. But Doc didn't fully explain why because the watch he was wearing at the time beeped, warning him that the DeLorean's return was only seconds away.
The car suddenly appeared where Doc and Marty were standing and screeched to a halt as a frozen shell. Supercooled from traveling through time, the gullwing door was troublesome for Doc to open while using his hands. Inside the car, Einstein was unharmed, much to the surprise of Marty. Doc then showed Marty the interior and its controls.
While inputting dates on the keypad, Doc used July 4, 1776 (the date the American declaration of Independence was signed) and December 25, 0000 (the date of the birth of Christ) as examples, before inputting "a red-letter date in the history of science, November 5, 1955". From there he left the cockpit of the DeLorean and reminisced about the past, particularly about Old Man Peabody owning the land that is now Twin Pines Mall and his pine tree farm.
Trapped in 1955
Soon after a new pellet of plutonium was inserted into the time machine, the Libyans who he stole the plutonium from intervened in a Volkswagen and shot Doc dead. Marty ran into the DeLorean to try to escape the Libyans. Marty accidentally turned the time circuits (still set to 1955) on while shifting, and as he avoided being destroyed by a rocket-propelled grenade, he sped up to 88 and entered temporal displacement. Suddenly, Marty went from a mall parking lot in 1985, to a field in 1955, and the DeLorean crashed into a scarecrow and then the Peabodys' barn.
For a moment, Marty was stunned, and the Peabody family ran from their house to the barn to investigate. Believing that the vehicle was from another world, they screamed in horror as Marty lifted the gullwing door and stepped out, dressed in a radiation suit. Marty was almost shot from the buckshot of Otis Peabody's shotgun, and ran back to the safety of the time machine, floored the accelerator, and smashed through the doors of the barn. After escaping from Peabody's shotgun, the car ran over one of the two pines that Peabody had been growing. This was the first effect of Marty's trip into the past that would alter the future (the "Twin Pines Mall" would become the "Lone Pine Mall").
Marty pulled the DeLorean onto a highway that ran by the future site of Lyon Estates. He immediately stopped and viewed the undeveloped land stretch far out into the distance, questioning whether or not it was a dream. A meter in the DeLorean indicated that it was out of plutonium, and the car shut down. Marty failed to get it running again and decided to hide the DeLorean behind the Lyon Estates sign, covered by a few shrubs, and walked the two miles to town.
After convincing the 1955 Doc that he was indeed from the future, Marty and Doc went back to the site to recover the time machine. Doc opened the door and turned on the flux capacitor which he had envisioned after his fall earlier that day. The DeLorean was driven back to Doc's garage where it was hidden under a dropcloth until the night of the thunderstorm, November 12.
On the 12th, Doc brought the time machine to Courthouse Square in downtown Hill Valley, and started working on the cable assembly that would harness the impending lightning strike. Arriving late, Marty was briefed by Doc, just as the storm moved in and took down a tree. Marty drove the DeLorean to the starting line at the Bluebird Motel, and inserted a tall connecting hook into the flux capacitor. He then waited for the alarm to go off while Doc reconnected the cable, and decided to reset the controls to arrive 11 minutes earlier than scheduled. With that, the engine suddenly died, and left Marty trying to restart it. Marty finally (and unexpectedly) succeeded in restarting the engine after head-butting the horn in frustration, and took off. The DeLorean reached the cable just as the lightning struck, and Doc made the connection, sending the time machine back to 1985.
In 1985, Red the Bum was awoken by the sonic boom of the DeLorean, followed by the sound of a crash at the Town Theater. Marty jumped out of the icy time machine to check out downtown and to verify that he had gotten back to the future, and back to his normal year of 1985. Returning to the car to save Doc, Marty tried to drive off and the engine died once again. This was the last time in the trilogy that it had done so. The Libyans passed him on the street, and Marty ran back to the mall. There, he saw the first DeLorean make the jump to 1955, with the terrorists' van crashing into a photo booth. Originally believing he was too late, Marty was in grief, then surprise. Doc recovered, and revealed that he was wearing a bulletproof vest, having read the warning letter that Marty had written 30 years earlier.
Doc returned to downtown to start the DeLorean up, and drove Marty back to his home in Lyon Estates. Doc told Marty he would go roughly 30 years into the future, "a nice round number". Doc backed the DeLorean up with enough room to reach 88 mph on the street and vanished in three sonic booms.