I saw this for the first time last night - bank hol 'is there anything on? not really, let's look at this' moment.
It's very - simple, isn't it. A simplified version of crime fiction, that's really about enjoying having a few 'heritage' actors and screen and looking at the vicar's face (and bod). Is that it?
It was obvious from the start who had 'done it' - the one who presented as deeply horrible, immediately. Why was obvious too.
The vicar seemed very much like a present day person saying the lines, conveying present day feelings and attitudes, not like someone making any effort to act a character from that time.
The whole 'can I have an affair that results in re-marriage post-divorce' plot, well duh, you're a vicar. Quite liked the (presumably gay and adoring) curate telling the woman we can all feel but not always act, which she didn't 'get' as coming directly from his pov.
We got to the second ad break, said 'well we know what's happened and who did it, shall we go to bed?', which DP did. I sat it out. Not exactly gripped though!