I've watched the wholes series via iPlayer and was immediately struck by how different the style was as a series made in the late 80s(?) compared to how they have adapted le Carré in recent years.
And wonder also whether because it was make relatively soon after the period covered in the book it is a more accurate reflextion of British society at that time. (Although suspect it is really about a certain class of English people.)
But mainly posting to ask if anyone else has watched or is watching. Or read the book
This is because on one level it isn't about spying at all it is about ... what? I just didn't grasp it at all! 
How early childhood forms us? Or that some people are just natural cons, and some people dont mind being conned when it suits their agenda or ....
Thanks
https://www.bbc.co.uk/iplayer/episodes/b008dqld/a-perfect-spy