In order to save the world from a nuclear holocaust in 2045, Doc Brown must push the technological age back at least 50 years preventing Mattel Hoverboards and Mr. Fusion from being created.
1993
2017
1995
2021
2018
2023
2020
2019
2009
1996
1976
2003
2013
1985
1991
2010
2022
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