The first draft screenplay of Back to the Future Part III was written in 1988.
- The screenplay opens in Doc's study. Doc reads the note his future self wrote.
- Doc recollects to Marty how he got into science — when he was eleven, he stuck his finger in an electrical socket. (This was presumably changed for fear children might imitate this.)
- Doc's tombstone reads: "Here lies Emmett Brown. Date of birth - unknown. Died - April 13, 1888. Gunned down by a dirty coward whose name does not deserve to be remembered. Erected in loving memory by his beloved Clara".
- While fixing the DeLorean, Marty noticed a photo of Doc with a woman. Doc tells her she is Jill Wooster, the daughter of the Dean of the Hill Valley University. Doc tells Marty that she also likes Jules Verne, and they both went to Pismo Beach.
- While Doc and Marty were busy, Dean Wooster and his cohorts Cooper and Mintz tell him that he must participate in one of three projects: the Edsel car, chemical warfare, or Xerox (which Doc pronounces "X-rox"). Doc however has no interest in any of the projects and refuses to do so. The Dean threatens that his relationship with his daughter will be damaged unless he cooperates with them. The next day, Jill tells him to do it for her, but Doc still refuses. Then, Jill angrily walks out of his life, adding that she never liked Jules Verne. Heartbroken, Doc trashes all his photos of himself with Jill and swore to never love again.
- Marty left the DeLorean at Indian Rock Park, which was inhabited by an Indian tribe.
- Seamus McFly is named Angus George Douglas McFly.
- In the original timeline, Clara fell off a cliff which was named Clayton Cliff.
- While reading the note, Doc recalls spending summers at his uncle Abraham Lathrop's place (that's where Doc got his middle name). Doc's mother's name was Sarah.
- Doc mentions that after he sends Marty back to 1985 (again) he will "go out on a binge, get completely plastered, have a great time, and forget all about everything."
- Doc's mother's family, the Lathrops, have lived in Hill Valley since at least the 1880s.
- Clara was a schoolteacher who was widowed in Silver City.