In 1927, "Bathtub Jim" McFly used a distillery named Mr. Gin to distill gin for the Benedict gang in Chicago, Illinois, during Prohibition. Doc used Jim "Zipper" McFly's Mr. Gin to distill juniper berries to treat the eye infection of his dog, Einstein.
"Mugsy" Tannen tried to get "Zipper" McFly to brew a lite gin, which he described as having all the taste of regular gin, with half the calories. Marty McFly told him that the idea was interesting, and ahead of its time.