Time loop

A Time Loop is a fictional situation where time runs normally for a set period (usually a day or a few hours) but then skips back like a broken record. It is a common plot device in science fiction.

Often, when the time loop "resets", the memories of all experiencing the loop are also reset (i.e. they forget all that happened). Plot is advanced, however, by having one character become aware of the loop through deja vu.