Fog, Victoriana, Poe. This oddity eschews telling a story in favour of pure atmosphere. Not in the usual Avengers sense of pretty home counties villages, old fashioned pubs and red telephone boxes, but by filling a studio set with fog, barrel organs and gaslights.

Supposedly there’s some kind of disarmament conference going on, but in the twisted foggy logic of this episode, delegates wander alone down badly lit alleyways. And once again, Mother’s organisation demonstrates its extraordinary incompetence, with Steed and his partner losing one of just 5 delegates between the station and their car. Worse still, Mother’s reaction to Tara’s concern is “Oh I shouldn’t worry” and said diplomat is skewered by the gaslight ghoul…

The lady selling ‘lucky white heather’ reminded me of the Steed’s contact in The Frighteners who gave him his buttonhole – though it seems unlikely this could have been a reference.

There’s plenty of bad lighting in evidence. And to save the cost of building another ridiculous HQ for Mother, they have him rider around in a union jack buggy. If it’s not the most stupid of Mother’s HQs yet, that’s only because of the quality of the competition. The Black Museum is not very scary (and the sets within it look only slightly more artificial than the ‘real’ streets).

It has all of the faults of series 5 (muddy visuals, uninspired plotting, paucity of location) without the redeeming presence of Diana Rigg.

But the very worst is saved for the tag scene which Mother gate crashes. It makes utterly no sense anyway, but in view of the weird arrangement of Tara’s apartment doors Steed’s suggestion that someone could have driven in because she “left the front door open” is not even conceivably ludicrous. What, at the top of the stairs?