I watched the first two seasons of "The Bletchley Circle" and tried the third season on BritBox. I could not get past the first episode for all the reasons outlined in the article.
A proper old-fashioned stinker: ITV’s The Bletchley Circle – San Francisco reviewed
After just one episode, The Bletchley Circle: San Francisco (ITV, Wednesday) seems certain to stand out from the crowd. In an age when most television dramas range from the perfectly fine to the extremely good, it already looks like a proper old-fashioned stinker.
Admittedly, one of its more obvious problems is bang up-to-date: by adhering so spinelessly to the mantra of ‘women and black people good, white men bad’, the programme not only creates an overwhelmingly dreary sense of déjà vu, it also deprives itself of any possibility of genuine dramatic tension. But there are plenty of more traditional flaws too, including such classics as wooden dialogue, leaden humour and a plot of impressively po-faced preposterousness.