I thought this was the best episode of the series so far. The mystery was engaging and challenging. I have to agree that, much as I love Darlene's character, she did overshadow Naomi somewhat. Izzy was less irritating this week. Hard to believe that she's played by Kate O'Flynn, who was superb as a returning character in Father Brown. I loved the Cornelius StBrice character. Hope we see more of him. They seem to be playing down Neville's allergies, it's as if the scriptwriters have forgotten all about them, thankfully.