Enough reviews about the series, I enjoyed, excellent, intriguing.
I want to write in response to lots of queries over the ending!
I believe that the daughter had taken part in a make up of the plan that the secret service had inklings about, and that her writer friend was also involved with MI5/6 and had been able to feed in to the comedy episode shown on the TV which brought all the dastardly plans to an abrupt end, after the daughter had unwittingly revealed a conversation with her dad.
So it all makes sense if you take this into account.
The missing son storyline, which again a lot of people were perplexed by, I believe again was that he had provided information to MI5/6 as soon as he had become aware, and had been advised to disappear to protect himself, and his preferred way of vegan life.
Overall, as good as any Agatha Christie. Kept you intrigued and confused right till the end!
I loved the acting, especially the lead lady.