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.
2003
1994
2001
1987
2013
2014
2022
2002
1991
1965
2018
2005
2009
1982
1986
2000
2008
1972
1979