History Film / BackToTheFuturePartIII

* ArtisticLicenseHistory: Okay, so they didn't have plumbing and fluoride and water treatment plants, but people in the past weren't drinking ditch water, not if they could help it. They had wells and springs; they ''knew'' that healthy water was ''clear'' water.

* LoveAtFirstSight: Doc and Clara, though Doc's skeptical before they meet when Marty says that this happened with him and Jennifer.

** A downplayed, non-lethal variation when Marty prepares for departure to 1885. Rather than send Marty back on September 1, 1885 -- the day his counterpart wrote his letter to Marty -- 1955 Doc instead sets the "Destination Time" to the very next day (September 2, 1885). While it's not outright stated in the film, the implication is that they ''can''t send Marty back any earlier. They ''need'' 1885 Doc to complete his preparations to seal the [=DeLorean=] in the Delgado Mine and entrust the letter to Western Union. Going back any earlier risks disrupting that chain of events, which could then jeopardize their recovery of the [=DeLorean=] in 1955.

** A downplayed, non-lethal variation when Marty prepares for departure to 1885. Rather than send Marty back on September 1, 1885 -- the day his counterpart wrote his letter to Marty -- 1955 Doc instead sets the "Destination Time" to the very next day. While it's not outright stated in the film, the implication is that they ''can''t send Marty back until a point ''after'' 1885 Doc has completed his preperations to seal the [=DeLorean=] in the Delgado Mine and entrust the letter to Western Union. Going back any earlier risks disrupting that chain of events, which could then jepoardize their recovery of the [=DeLorean=] in 1955.

* CantKillYouStillNeedYou: While it's not explicitly stated, Marty's biggest handicap in the final showdown with Buford is that, obviously, he ''can't'' just kill him. Apart from whatever else his impact on Hill Valley will be in the years to come, Buford ''needs'' to live long enough to continue the Tannen bloodline (and ensure Biff will eventually be born, thereby setting up his roles in the first two films). Killing Buford will only screw up the timeline worse than it already has been at this point in the Trilogy.

* BewareTheNiceOnes: Doc Brown is an intelligent, altruistic scientist who spends the entire series trying to do what's right, help his friends better their lives, and who wouldn't hurt a fly. However, the moment he sees Mad Dog and his friends trying to lynch Marty, he promptly shoots the rope and they takes aim right at Tannen's head. He's fully prepared to drop the hammer on him if that's what it takes to save Marty, and Tannen doesn't try to push it. Also a definite case of LetsGetDangerous.

* ArtEvolution: While the basic [=DeLorean=]time travel effect remains unchanged, it has also been tweaked for the final film. The effect takes longer to build up and is more chaotic. This could be justified in-universe between the more primitive 1955 Time Circuit repairs and the time machine now being 70 years older and struggling to keep up.

** During the beginning of the final showdown with Buford, pay close to attention to not only how Marty moves, but how he removes his gunbelt. He's moving carefully and delibertely; his hand's even inside the poncho, as if it's holding on to something. [[spoiler:Marty's trying to hide that he's wearing a homemade bulletproof vest under the poncho.]]

** Back in the first movie, Doc's exposition established that the genesis of the Flxu Capacitor came while he was hanging a clock above his toilet. Doc slipped, banged his head, and when he came to the Capcictor was in his head. When Marty tries to bring 1955 Doc up to speed on the events of Part II at the beginning, Doc retreats into his bathroom. When he finally comes out, you can see the clock and toilet in the background (and Bob Gale's DVD Commentary confirms this was an intentional, subtle callback).

** And Doc's outfit at the end looks something like that of Professor Marvel in ''Film/TheWizardOfOz''.

* CantKillYouStillNeedYou: While it's not explicitly stated, Marty's biggest handicap in the final showdown (to say nothing of the entire preceding film) with Buford is that, obviously, he ''can't'' just kill him. Apart from whatever else his impact on Hill Valley will be in the years to come, Buford ''needs'' to live long enough to continue the Tannen bloodline (and ensure Biff will eventually be born, thereby setting up his roles in the first two films). Killing Buford will only screw up the timeline worse than it already has been at this point in the Trilogy.

* NamedInTheSequel: The name of Doc's dog in 1955 goes unmentioned in he [[Film/BackToTheFuture1 first film]], but the scene at Doc's house at the beginning reveals his name as Copernicus.

** Towards the end of the film, the members of Needles' crew are played by a member from each of Biff (and Griff's) gangs in 1885, 1955, and 2015.