TIMELOOP
Time loop
A time loop or temporal loop is a common plot device in science fiction where a certain length of time repeats over and over. When the time loop "resets", the memories of most characters are reset, and behave as though they're not aware of the loop. The plot is advanced by having one or more central characters retain their memory or become aware of the loop through déjà vu.The above text is a snippet from Wikipedia: Time loop
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