Another of the curious adventures of the young Mary Russell and her somewhat older husband Sherlock Holmes.

I was pleased to find that this book steered clear of theology for the most part as a tendency to give her readers an overdose of theology is the only thing that I dislike about King’s books. The letter in the title has nothing to do with Mary Russell but refers to a letter written by Mary Magdalene. Although this forms part of the plot it’s not concentrated on to the exclusion of everything else and Russell and Holmes get on with more interesting things.

My major problem with the plot of this book is that there’s too much happening which turns out to have nothing to do with the main storyline. The investigation goes off at a tangent and much of the story is taken up with investigating a shoal of red herrings. What happens is interesting and I liked the insights into 1920s feminism but I couldn’t help feeling that I’d been looking in the wrong place while the action took place elsewhere.

This third book in the series wasn’t as entertaining as the previous one and I hope the next book is stronger.