The Back to the Future I timeline - anomalies

Cracked have posted one of their amusing video's regarding a flaw with the first Back to the Future. Of course there are several, but the flaw they point out took me some time to understand. In the end I laid it out as follows.

We start with the original timeline and its inhabitants that I'll refer to using a subscript OT. In this timeline Doc_OT hits his head invents the flux capacitor, and build the time machine. Marty_OT watches his father George_OT being picked on by Biff_OT and hears about how his mother Lorraine_OT fell in love with his father after being hit by her father's car. Now things get fun.


Marty_OT sees Doc_OT get shot by the Palestinians_OT jumps into the time machine and ends up back in 1955. At this point using the theory explained in Back to the Future Part II a new timeline is created. As this is one where Marty's family end up successful I'll refer to it as ST.

Marty_OT rescues George_ST and Lorraine_ST subsequently falls for him. Marty_OT meets up with Doc_ST to try to get the time machine working. As an outcome George_ST punches out Biff_ST causing Marty_OT to exclaim that his father had never done that.

Marty_OT and Doc_ST get the time machine working and return to just before Doc_OT was killed. However Marty_OT doesn't make it in time and thus sees Doc_ST getting shot and Marty_ST jump into and use the time machine. The Palestinians_ST crash and burn and Marty_OT rushes over to find Doc_ST unharmed thanks to the knowledge that Marty_OT brought back to him.

Marty_OT then discovers that his parents are successful and Biff_ST cleans his car.

The question posed by Cracked is what about Marty_ST. At first this seems a closed loop, but it's a whole different Marty that leaves the 'second' time around. Marty_ST grew up with successful parents and siblings and on stories of how George_ST stood up against Biff_ST to help Lorraine_ST. Cracked propose the Doc_ST bumps him off. There is another option.

When Marty_ST pops into the past we get a third new timeline NT. Suppose Marty_ST doesn't save George_NT or get involved with his family the outcome would be the same as the OT. Worse yet Marty_ST would return to find Doc_NT to be dead and George_NT working for Biff_NT. On the other hand If Marty_ST did take a hand in things then NT would be identical to ST.

From our outsider's perspective though we see no changes created by Marty_ST thus, if the Doc's take on time travel from the second film is correct, Marty_ST made no changes and must have died. This means Doc_ST purposefully befriended Marty_ST so as to get him into the time machine and be sent 4.5bn years into the past or whatever because otherwise we'd have Marty_OT and Marty_ST existing at the same time which could cause the destruction of the entire universe.

In the second film things get worse We're in the ST universe. Doc_ST takes Marty_OT and Jennifer_ST into the future to meet with Marty_OT's son. So far all players apart from Marty are ST.

However Biff_ST takes the time machine back to 1955 to give his younger self (also Biff_ST) the Sport's Almanac. Somehow he returns to the Future_ST despite technically this future no longer existing. With the handing over of the Sport's Almanac we now have the BiffWorld Timeline BT. With Biff_ST being able to return to the Future_ST there's a suggestion that the timelines don't change instantaneously.

Marty_OT Doc_ST and Jennifer_ST return to 1985 and find themselves in the Biffworld Timeline. Doc_BT is in an mental institution and Marty_BT is away at school.

They both return to 1955 and wait for Biff_ST to hand over the almanac. As Marty_OT already exists here this is in fact still the Successful Timeline. Marty_OT and Doc_ST do nothing to alter events regarding their present selves thus preserving the ST or at least creating a new timeline that is identical to the ST.

In the third film things get even worse. Doc_ST ends up in 1885, but this creates a whole new timeline I'll call Western Timeline WT. But this new timeline must create a timeline either identical to our original (thus allowing Marty_OT to go back and change it) or one identical to the Successful Timeline allowing our Marty_OT to drop back in and substitute for Marty_ST.

However given that both Marty_OT and Doc_ST make the same reference to the ravine name we now have Marty_WT who calls the ravine "Eastwood" watching Doc _WT being shot. As Doc_WT never met Marty_OT he's totally dead unless Marty_WT alters the past which he could do given that Doc_WT would not know to kill him to preserve the timeline.

Marty_OT returns to the Western Timeline evidenced by the change in ravine name, but technically this overwrites the alterations made creating the Successful Timeline, unless Marty_WT makes the changes, but where does he return to?


A way around all this is to take that delay in the time shifts into account from Part II. Marty_OT returns from 1955 to the Original Timeline to see himself jump into the time machine; the timeline then shifts to the Successful Timeline with Doc_ST being alive etc. However this doesn't explain the instant shift to the Western Timeline and the change in the ravine name.

Ah artistic licence.