"Series conclusion" refers to the final part or ending of a series or story. It is the last installment that ties up loose ends, concludes the plot, and brings the narrative to a satisfying end. Full definition
This is as dour and disappointing a potential series conclusion as one could ever (or should I say, never) have hoped for. (qwipster.net)
I recommend reading Part One: Scaling Real Relationships, and Part Two: Empowering Activists with Leadership before reading Part Three, which is also the series conclusion, below. (epolitics.com)
I know that many fans are afraid of spoilers, so all I'll say is that Mockingjay is a page - turner (duh); I am not disappointed with what I've read (aren't you always worried you'll be disappointed after looking forward to a series conclusion for so long?) (bookpage.com)