Black Mirror had been batting a thousand until right after the first episode of the last season (USS Callister, which was great). What followed got pretty preachy, which unfortunately sacrifices the interestingness of the plot, like in Black Museum. (Hang the DJ was really good.) Still, given the strength of the first 3 seasons, the next installment was going to get our attention.
What is innovative about BM Bandersnach, is that you, yes you the viewer, must make decisions on what the character should do. Your options are limited, but you are very much a part of this story.
Love the Brits.
Overall - Must Watch