September 7 is the 250th day of the year.
- "Doc" Emmett L. Brown dies from a gunshot wound received from Buford "Mad Dog" Tannen on September 5th.
- Doc Brown arrives in the early morning at the Palace Saloon for a drink of whiskey.
- Doc tells the crowd inside the saloon about the future and his loss of Clara Clayton while the barbwire salesman overhears him.
- Heartbroken, Clara decides to leave Hill Valley for San Francisco, purchasing one-way ticket.
- 7:50 AM: Marty McFly arrives at the Palace Saloon and convinces Doc to leave Hill Valley to catch the train, but Doc drinks the whiskey and passes out.
- The train arrives at the station, picking up Clara.
- 8 AM: Buford arrives at the Palace Saloon and challenges "Clint Eastwood" to come out.
- 8:05 AM: Doc wakes up and he and Marty attempt to escape out the back.
- 8:10 AM: Buford's gang catches Doc and they hold him hostage until Marty comes out.
- Marty walks into the street and he tries to forfeit the duel.
- Buford shoots Marty and believes he is dead.
- Marty, protected by the bulletproof vest he made from an iron stove door, uses it to knock out Buford and knocks him into a manure cart.
- Buford is arrested by James Strickland's deputy for yesterday's robbery.
- Marty and Doc race on horse to catch up with the locomotive, meanwhile Clara has stopped the train to return to Doc after overhearing the barbwire salesman on the train.
- Marty and Doc intercept the train before the switch to Carson Spur.
- They uncouple the locomotive from the cars and take it down to the DeLorean time machine.
- Marty and Doc proceed with the experiment and Clara catches up.
- Doc saves Clara trying to reach him and Marty inside the DeLorean reaches temporal displacement just before the Shonash Ravine bridge.
- The locomotive plunges off the incomplete bridge and into the Shonash Ravine, and is destroyed in an explosion.
- Doc and Clara reunite.