- " Doc turned around [in the driver's seat of the DeLorean]. The dog was playing with something in the back seat. / 'Einie, get that junk out of your mouth!' / Doc pulled the crumpled silver bag from between Einstein's teeth. / A silver bag? Something tugged at the back of Doc's mind. Where had he seen a silver bag before? Where did that dog find this stuff, anyway?"
- —From Back to the Future Part II by Craig Shaw Gardner (quote, page 95)
When Marty McFly bought the Grays Sports Almanac at the store on October 21, the saleswoman put the book into this bag, along with a receipt. Emmett Brown disposed of the almanac by throwing it into a trashcan, rather than making use of a Litter Bug that happened to be nearby, where it was found shortly afterwards by Biff Tannen.
Doc discovered the bag, with the receipt still inside, in the DeLorean time machine, along with the top of Biff's cane, after he and Marty left 2015 for 1985, but instead found themselves in a nightmarish alternate reality.