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.
2010
2025
2020
2013
1999
2005
2024
2019
2016
1980
1987
1989
1991
2023
2000
2015
1949
2021
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