James Blake was doing okay. Better than okay. A working class lad from Lisburn in Northern Ireland, he set up his own digital marketing agency. At the age of 30 he was earning enough to buy sports cars and swish watches. He posted photos of himself on social media, enjoying life to the full.

One way and another, James Blake had taken a good bite out of the internet. But then the internet bit back.

Alerted by a comment left on his website, Blake discovered there were lots of “Fake Blakes” out there, people using his image and photos to con others out of money, a process known as “catfishing”.

“Even my dog Lily was being used in a Go Fund Me,” he says, still recoiling at the cheek of the scammers.

What happened next is recounted in Hunting the Catfish Crime Gang (BBC3, Monday, 9pm), possibly the best-titled programme out next week.

After he issued an appeal on social media, Blake was contacted by three women who had corresponded with fake accounts using his identity.

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“They’re all relatively quite young. They’re not … old women. They’re not tech illiterate, ” he says, summing up the common but mistaken view of those who get scammed. “It can happen to anyone,” a detective specialising in “romance fraud” tells him.

It happened to Kate, who was conned out of £30,000 by someone posing as Blake. What sort of a person could do that, he wonders, and how do they manage it? After all, we like to think we would spot the rip-off merchants.

But then an expert takes Blake through the methods used to “groom” victims. While you might spot the obvious cons, others are more sophisticated and rely on proven manipulation techniques. The scammers work from carefully worked-out scripts for a reason.

There have been more than a few documentaries on cyber crime lately. Blake’s film stands out because he’s a likable sort, and because he takes the story further than others, tracing some of the crimes to their source. I wouldn’t be surprised if we see his face again - fronting another documentary.

BBC2 recently showed the last part of the acclaimed series, Rise of the Nazis, which featured efforts to bring German war criminals to justice.

The Devil's Confession: the Lost Eichmann Tapes (BBC2, Sunday, 9pm) can be seen as an addendum to that, but it is a fascinating two-part series in its own right.

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Adolf Eichmann, who had been in charge of sending Jews to the death camps, was one of many Nazis who fled to Argentina after the war in the expectation of a peaceful retirement.

Eichmann was so sure that he was safe he brought his family over from Germany to join him. But he had been found. Israeli agents were dispatched to snatch him from Argentina and bring him to a courtroom in Jerusalem where he denied all charges against him.

As other Nazis had done, he claimed to be following orders and had known nothing of the camps and the murders of millions. To the court, to the world, Eichmann presented himself as a minor functionary. He looked like “a lowly post office clerk”, said Attorney General Gideon Hausner.

Yet some years earlier, while in Buenos Aires, Eichmann had been interviewed at length and on tape by fellow Nazi Willem Sassen, a journalist. On the tape, Eichmann went into details about what he had done, even boasting of his efforts.

What happened to these tapes, how they were discovered, lost, and then found, sounds like a work of fiction but is all too true.

Using a mix of interviews with historians, dramatic reconstruction, footage from the time and the Sassen tapes, The Devil’s Confession pieces together the astonishing story. Among those interviewed is one of Sassen’s daughters, who remembers the sinister visitor to her childhood home, the one so keen on the sound of his own voice.

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Every now and then it is worth having a search through the BBC iPlayer to see what treasures have been added lately. There is so much there you could probably watch from now until New Year 2030 and still barely make a dent.

This week’s recommended golden oldie is Hamish Macbeth (BBC4, Wednesday, 10pm, all series on iPlayer). Come with me back to the year 1995, a simpler time when audiences were content to spend their evenings in the company of the titular Highland copper (played by Robert Carlyle) and his faithful hound, Jock.

As can be seen from the opening titles, packed as they are with tartan, bagpipes, seafood and shots of misty lochs, Hamish Macbeth was never shy in proclaiming its Scottish roots.

Carlyle, fag in hand, lends some heft to the light material, though now and again a serious storyline finds its way through, as in the first episode, The Great Lochdubh Salt Robbery, which touches on domestic abuse.

Decide for yourself if Hamish Macbeth has aged well. Definitely one for Carlyle watchers, though. A year after Sunday night audiences took Hamish to their hearts, Carlyle appeared in a little film called Trainspotting playing a character by the name of Begbie. Let’s just say Jock would not have approved.