I have loved seasons 1-4 of the Masterpiece Poldark series. The photography, the sets and the landscape, are truly magnificent. The actors are appealing, gorgeous, and very fine. The script and the screenplay are skillfully written, mainly because of following the writing of Winston Graham, whose novels are the basis of the series.
Season 5 is a departure from the earlier seasons of Poldark because of the strange decision to stop following the original novels and make up a story line that seems to be based on the Poldark tv series rather than Poldark novels. With all the character development having been taken care of in prior seasons, Ross, Demelza, and the others seem to be locked in place, trying to finish out their dramatic parts. It seems over in most ways. So disappointing and anticlimactic.
Plus the script is overly complicated, probably due to the fact that there is no coherent plot, too many new and unsympathetic characters, and a sense of "trying too hard to please the fans" attitude.
I doubt if I will add season 5 to my video collection.