The X-Files: 4x19
Synchrony
A case involving a strange old man warning two scientists of events in the immediate future which come to pass (and the use of their experimental flash-freezing compound that does not exist yet) has Mulder believing that one of the scientists has come from the future to stop his own scientific breakthrough from becoming reality.
4 - 1Herrenvolk (2) Oct. 04, 1996
4 - 2Home Oct. 11, 1996
4 - 3Teliko Oct. 18, 1996
4 - 4Unruhe Oct. 27, 1996
4 - 5The Field Where I Died Nov. 03, 1996
4 - 6Sanguinarium Nov. 10, 1996
4 - 7Musings of a Cigarette Smoking Man Nov. 17, 1996
4 - 8Tunguska (1) Nov. 24, 1996
4 - 9Terma (2) Dec. 01, 1996
4 - 10Paper Hearts Dec. 15, 1996
4 - 11El Mundo Gira Jan. 12, 1997
4 - 12Leonard Betts Jan. 26, 1997
4 - 13Never Again Feb. 02, 1997
4 - 14Memento Mori Feb. 09, 1997
4 - 15Kaddish Feb. 16, 1997
4 - 16Unrequited Feb. 23, 1997
4 - 17Tempus Fugit (1) Mar. 16, 1997
4 - 18Max (2) Mar. 23, 1997
4 - 19Synchrony Apr. 13, 1997
4 - 20Small Potatoes Apr. 20, 1997
4 - 21Zero Sum Apr. 27, 1997
4 - 22Elegy May. 04, 1997
4 - 23Demons May. 11, 1997
4 - 24Gethsemane (1) May. 18, 1997