- "He [Marty] heard a noise from the cave behind him — a growling noise. / Marty looked over his shoulder at the cave mouth, and a rushing grizzly bear! / 'Yaaah!' Marty remarked. / The grizzly bear ran toward him. / Marty ran too. His boots fell from his grip, but there was no time to stop and retrieve them. Then his fancy, white, ten-gallon hat flew from his head. Too bad. Marty had a bear on his rear end — the kind of problem that only had one possible solution. / Marty ran like hell."
- —From Back to the Future Part III by Craig Shaw Gardner (quote, pages 43 and 44)
A bear is a mammal that has a large body with stocky legs, long snouts, small rounded ears, shaggy hair, paws with five non-retractable claws, and short tails.
Outside the McFly farm in 1885, when Marty McFly arrived in the DeLorean time machine, a grizzly bear woke up in its cave and investigated the noise. Upon seeing Marty, it stood up and challenged him, before chasing Marty out of the cave. Marty threw his boots to the bear, which it began to sniff.
Afterward, Marty fell down the opposite hill and knocked himself out. When he came to at the McFly farm, he spoke of being chased by a bear.
In 1850, as Daniel Clayton and Martha O'Brien crossed the Oregon Trail, they converged in northern Wyoming in what would later be Yellowstone National Park. Martha and Verne Brown were chased by a bear. Doc Brown told them to sit on a buffalo hide atop Old Faithful. They were then lifted up by the geyser and were saved by a glider flown by Doc and Daniel Clayton.
- In Super Back to the Future Part II, the password to reach Round 4-2 is 'bear'.
- Back to the Future Part III
- Super Back to the Future Part II (Password)
- Back to the Future: The Animated Series