WONDER what goes through the minds of celebrities who are approached to do Who Do You Think You Are? (BBC1, Monday, 9pm). Maybe some think, “I’m so boring, there will likely be nothing interesting in my past.” More likely it is, “Hurrah! I'm going to look dead clever wearing white gloves and peering at documents through a magnifying glass.”

Boy George, having lived through some interesting times himself, had nothing to lose from a chauffeured drive down memory lane. Describing himself as “the pink sheep of the family”, the Londoner considered his Irish Catholic roots and predicted “a lot of mascara running” ahead.

Sure enough, by ten minutes in, George, now a Buddhist, was welling up at the kitchen table as he and his mum talked about nan. Family legend had it that she had been found wandering the streets of Dublin at six-years-old and sent to an industrial school to learn a trade.

When George arrived in the fair city he discovered that she had been picked up by charity workers a mere hop, skip and jump away from her front door. She wasn’t lost at all. Subsequently lost to her family, yes, but not lost. Given the slum conditions in which many poor families lived, he learned, some worthies looked upon it as a kindness to remove a child from their home.

“I’m proud and I’m sad,” was George’s verdict at the end of it all, which is perhaps the best one can hope for. The programme ended, fittingly, with him singing with a local group. No longer the pink sheep of the family, standing alone, but a part of something bigger than any of us, history.

Unforgotten (STV, Sunday, 9pm) is back and with it the best detective partnership since Morse and Lewis (put a sock in it Turner and Hooch fans). DCI Cass Stuart and DS Sunil “Sunny” Khan (Nicola Walker and Sanjeev Bhaskar) investigate murders from long ago where the body has only just been discovered.

The most admirable thing about Unforgotten is that it is not afraid to be sombre. Like the rest of its kind, it exploits misery for entertainment, but it is all done in the best possible taste. Think of it as the John Lewis of murder mysteries.

As we approach the halfway point, this third series is shaping up nicely, with four male friends, a GP, a TV presenter, a salesman, and an artist, coming under Cass and Sunny’s gaze. I don’t like the look of the TV presenter. Shifty sorts, telly folk, the only exception to the rule being critics, of course. You can take what we say to the bank. Or the gold bar shop. Did you know there were such places? Millionaire businessman Dave Fishwick introduced viewers to them in How to Get Rich Quick (Channel 4, Monday, 8.30pm).

Dave, as he was fond of reminding us, is from Burnley. He’s like a northern Del Boy, able to buy and sell almost anything. But unlike Peckham’s finest he is extremely good at it. Once a labourer, he now drives the sort of car that small boys, and some big ones, run after in the street. His offer here was simple: bring him an idea, back it with your own cash, and he will help you make the most of it. The first volunteer was a council worker from Reading who decided her mum’s grub was so yummy they could sell it from a street stall.

The advice from Dave tended to fall into the screamingly obvious bracket, such as the importance of doing your homework before launching a new enterprise. Money was duly made. Not a fortune, but enough to keep work going on an extension to the family home.

The gold bar shop came along when Dave unveiled his next schtick: every week he will take Mags, a granny from Warrington, with him as he invests in various commodities. Mags' role is to ooh and ah at the wonder of all this fancy-dan capitalism in action.

This week Dave bought a small bar of gold, the size of a Freddo, for £3,325. Eight weeks later it had fallen in value by £230. I would have liked more of an explanation than it takes time for some investments to pay off, but one was not forthcoming. I’m also curious as to why Dave, if he has so much money, has elbow patches on his suit. Maybe that is why he has so much money.

The Bletchley Circle: San Francisco (STV, Wednesday, 9pm), about former codebreakers turning their hand to catching bad guys, takes the crime drama genre to new heights of ridiculousness. It reminded me of an idea The West Wing’s Sam had for a show about Pilgrim detectives. “By day, they churn butter and worship according to their own beliefs and by night, they solve crimes,” he told an unimpressed Toby. Where do I sign up?