On Call

Arthur Davisworth takes an anonymous call offering him a new sealing process that has already passed its trial stage at Sidwich and Reynolds. The price is ten thousand pounds. A process that has passed its trials is worth far more than that, which is exactly why the call is anonymous. It sounds like a gift, and the episode sets out to show why nobody should take it. The anonymous call is the kind of temptation the series loved: legal-sounding, and quietly wrong. There is bad blood here: Davisworth suspects Ronald Reynolds of having stolen his process once before, and the offer, from a voice he cannot place, looks like a way of getting him to buy back his own work.

Peter Graves plays Davisworth as a man who can feel the trap closing and is tempted anyway, and John Blythe's Reynolds is the colleague whose history hangs over everything. Maggie McCarthy's Betty Jameson and David Sinclair's Bill Massey move through the company, while the squad, Watt, Hawkins and Evans, with Snow and Perry in support and Walter Gotell's Chief Constable Cullen looking on, tries to work out what is being sold and who is doing the selling.

Elwyn Jones wrote it, David Sullivan Proudfoot directed. The episode is at its best on the ethics of the deal: Davisworth's own position is not clean, and the show is honest about that, letting him squirm between greed and grievance.

It is an industrial story, all telephones and balance sheets, and the series did these very well, giving real weight to the question of what a man will pay to get back what he believes is his. It does not go in for chases or shootouts, and the restraint is the point. But the real theft here may have happened years ago, in the bad blood between two colleagues, and the episode knows which wound matters more. On Call is quiet, suspicious and thoroughly professional, like the officers investigating it.