A distinctly sci-fi episode, with our first diabolical mastermind of season 4. It’s a strong episode, concerned with automation, robots and artificial intelligence. It’s a well crafted tale too, though the script does rather shameless info-dump in a couple of places.

The science in this is not too far fetched (Armstrong believes miniaturisation will enable AI so advanced that machines will compose music) although some of the logistical issues are rather glossed over, as are the control and navigation systems for Armstrong’s inventions.  But though it’s a bit convenient, a really like the denouement and Steed’s clever, quick way of outwitting their brute force.

Also I like the solid ink pens (remember pens?)

In the opening there’s a monsters POV shot at the moment of the kill, something we haven’t seen since Second Sight and I think this is the first time it’s used before the title card.

Mrs Peel gets to demonstrate her knowledge of electronics again. She knows about karate too, showing up those foolish enough to underestimate her, in a plot strand that proves to be an enjoyable red herring.

There’s a distinctive gun ricochet sound effect that gets used rather frequently, but I think this is the very first time it’s been heard.

Burt Kwouk is back only three episodes after his last guest appearance, but with an 18 month gap that wouldn’t have seemed problematic (and anyway, nothing will touch Peter Arne playing a different role in two episodes back to back).

Steed’s umbrella has a camera in the handle.

There’s no special transport in the tag scene – Steed and Mrs Peel are in their own cars, and their  dialogue directly relates to the plot.