The McFlys of Hill Valley was a detailed hardbound book that Emmett Brown assembled, via both traditional research methods and time travel. It detailed the history of the McFly family in Hill Valley from Seamus McFly to Marty McFly and his immediate family. It was the purpose for Doc traveling to 1931, as information surrounding Marty's paternal grandmother Sylvia Miskin was mysterious. Unfortunately this trip led to Doc being jailed for arson, his younger self marrying Edna Strickland, Hill Valley becoming a dystopian society, and the city burned down by "Mary Pickford". After Doc and Marty's adventures, Sylvia was determined to be performing under the stage name "Trixie Trotter", and this information was incorporated into the book. Emmett gave Marty the book as a high school graduation gift upon returning to a corrected 1986.