I never warmed much to this series. The main problem is the lead character himself - an unlikeable tosspot who's seemingly convinced of his own supremacy and infallibility, while considering everyone around him to be morons.
The show is so formulaically written that it's become easy, in the last few seasons, to guess who the murderer is almost as soon as they're introduced. This episode sidesteps that problem by revealing the identity of the guilty couple early on. What's at issue is the true extent of the wife's cooperation. Having already repeatedly watched the Law & Order episode based on the same real-life case, the result is no surprise to me. But that obviously can't be blamed on the writers.
But the episode does have Lynley doing his usual thing of shouting a lot at people, in particular Havers. Especially in the latter seasons, when he's not barking or outright yelling at her, he's rubbishing her ideas or making snide little digs. It's a weird way to write your hero. And it's a weird way to write a supposedly strong-willed, experienced detective sergeant that she never stands up for herself and demands to be treated with basic decency and courtesy, senior officer or no senior officer.
One last thing: what's the point in making Lynley an earl if it has no bearing on anything? I haven't read the source books, where things may be different, but in the TV series his title is relevant only in that it's mentioned from time to time and his family has a large estate that we visit twice. Really, he could just be a commoner from a rich family and it would make essentially no difference at all to the stories. It seems strange to have a premise as far out there as your lead detective being a member of the Peerage and then not use it in any meaningful way. Just as examples, more investigations involving noble families, or Lynley socializing with his peers (pun intended) would have made the series more interesting and helped it stand out in a crowded genre where so many shows so closely resemble each other.
