If this is truly a sequel I would not go overboard with trying to explain everything that happened to a new reader. You should add reminders of what happened before to make sure that people retunring to the series know what is happening and to give enough context for someone new to the story to have a general idea of what is happening.
You might want to add a 'Previously on Quicksave' bit in fornt of the story to get all the important things out of the way as you will kill the momentum of the story if you do anything else and if this is intended to be a series the problem will just become worse with each following story.
#12335434, By sunjumper NaNoWriMo 2018
sunjumper 3,490 posts
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Registered 17 years ago