Another week, another toilet bowl to swab. This time out, Eve and the team were at the gaff of a human rights lawyer (played by Tim “Lord Percy” McInnerny) who’d been set on fire in the middle of his living room. Most workmates discuss hot-button issues around the watercooler. Not this lot – here, they pick apart the asylum system around a horrifically charred corpse.

On the suspect list was former Robin Hood Jonas Armstrong, but it turned out he was merely swapping Lincoln green for red herring. There was also an asylum seeker who Keith Allen got to fruitlessly chase for a while, proving in the process that he’s all Hale but no pace. Puffed out and demoralised, he put in a call to the Body Farm and confused Mike for Eve. I know Tara FitzGerald has a husky voice, but that’s just ridiculous.

Again, the biggest mystery yet to be explained is why the kitchen back at base is situated so close to the dissecting table. God knows what germs lurk on that draining board. Mike, meanwhile - who’s spent previous episodes unpacking equipment, packing equipment away again and walking around moodily with a Bluetooth headset in his ear - came into his own when he poured lighter fuel in a cadaver’s lap and set it ablaze.

Yet it was Rosa who, once again, proved her worth in the field — not that she gets much thanks for her efforts. “What was Rosa doing there?” wondered DI Hale. “Shouldn’t she be looking down a microscope or something?” Yeah, that’s the way to show gratitude when she solves all the cases week in, week out. Just stick to fretting about the price of chewing gum, eh, mate?

As with the rest of the series, the techie findings were exhaustively explained with lots of information about vascular dementia and pronounced cognitive decline. But there’s still little rapport among the squad – too much forensics and not enough chemistry, in my opinion.

They’ve got one more episode to turn it around. Can they achieve the seemingly impossible and serve up a decent storyline to match the science?