This is a great little story, taking the best of the grim realism of the early episodes (widowed Diana’s distress is a lovely bit of melodrama, and the ambulance crash is horrifying), plus a threat that remains topical today (biological warfare) and combining them with an eccentric mastermind typical of the Peel-era. Director Peter Hammond delights in shooting the music boxes clockwork toys that are his obsession from multiple angles. (The actual camera operating, however, is the most uncoordinated an ropey so far, which is saying something! The lighting and design are great though.) Bizarrely, this villain is played by Peter Arne who at this point sets what must be an unbeatable record for guest actors returning to play a different part – of 1 week! Arne played Gallion in Warlock (although in fairness, they weren’t recorded back to back, and he gives very distinct performances).

There’s a tease, with Cathy and Steed taking breakfast together in his flat. However, he reveals that he is staying at a hotel,  Cathy is borrowing his flat while house hunting.

We discover Steed and his organisation are not above hiring safe-crackers.

Some good fights – we don’t even have to wait for the showdown, Cathy gets throws around the grief-stricken widow she goes to interview, then stuck in to one of the baddies in Act II. And Cathy extricates herself from imprisonment without any aid from Steed (he claims to have been watching from the sidelines).