The Magician's Nephew

The title borrows a name from C.S. Lewis, but there is nothing childlike about the magic in this one. A series of deaths by poison sends Barnaby towards the Temple of Thoth, a local cult whose traditions look suspiciously like a motive. The poison comes from the dart frog, which is not the sort of thing you can buy at the village chemist, and the exotic method gives the whole inquiry an unusual flavour. Barnaby has seen stranger things in the county, but a poison dart frog is a new one even for him. The cult, naturally, insists the deaths are nothing to do with them, and the show enjoys letting them insist. The deaths are quick and quiet, which is more than can be said for most Midsomer methods.

The worshippers supply a compact cast of suspects. Stuart Wilson's Aloysius Wilmington and Dominic Rowan's Simon Wilmington are the family at the centre of it, with Sian Brooke's Christine Turner and Michael Fitzgerald's Hugo Cartwright orbiting them. Barry Jackson's Dr Bullard identifies the poison and earns his screen time, while Kirsty Dillon's WPC Gail Stephens and Jason Hughes's Ben Jones do the slog of the investigation. Laura Howard's Cully and Jane Wymark's Joyce keep Barnaby attached to ordinary life, which is more than can be said for the faithful of Thoth.

Michael Russell and Caroline Graham wrote it, Richard Holthouse directed. The episode is at its best when it leans into the oddness of its own premise, a handful of grown adults in a country house playing at ancient Egypt. The mystery unfolds at a steady pace, with the cult's secrecy doing most of the work. Each answer only opens the next drawer, and Barnaby works through them with his usual unimpressed patience.

Midsomer has hosted its share of strange religions over the years. But the Temple of Thoth sits comfortably among them; the rituals are nonsense, and the show knows exactly what it is doing.