Mixed tenses in storytelling refer to the use of different verb tenses within a single narrative.

Here's the transcript:- Howard: Hold on. Pause. Something doesn’t make sense. Look, in 2015, Biff steals the sports almanac and takes the time machine back to 1955, to give it to his younger self. But, as soon as he does that, he changes the future, so the 2015 he returns to would be a different […]