I haven't read the original books but decided to watch the show anyway, especially when I saw Samantha Bond as the main lead - I find her to be a wonderful actress.
At first I struggled a bit to find interest in the plot line as it was quite stagnant and there were constant dead ends that began to put me off of watching it altogether. Majority of the acting was well done though which turned me away from turning off the show! It was all very natural and most of the actors did a wonderful job bringing their characters to life. There were however certain parts where I slightly disliked both the dialogue and mannerisms of a couple of the actors but in the end, it didn't bother me too much.
By the second part of the story I became a lot more interested by the sudden plot twists and the pace that the story was now going. It definitely picked up near the end of the show, as the plot was finally coming together which made the ending very satisfying.
I don't watch modern murder mysteries often (between 2020 and present time) as I find that they can sometimes be very lost in translation from the original books that they're originally based on, so I didn't have high expectations but was pleasantly surprised with The Marlow Murder Club! It's a very good show for both casual murder mystery watchers (like myself) and crime fanatics that like a gripping, intricate storyline.