OLIVER HEMSLEY is a City millionaire in a hurry. He took his first job in the Square Mile at 18, set up his own firm at 26 and now, aged 42 but looking younger, he runs Numis Securities, one of London’s fastest-growing stockbrokers. All this has been achieved with an application and drive that seems completely at odds with his desire to keep a low profile.

His advisers have other ideas, however, and as Numis is quoted on the Alternative Investment Market, and pushing up its profits prodigiously — “£1m, £3m, £6m, £9m, £14m,” recites Hemsley langorously, “and I think we might get to £20m this year” — he obviously has a good story to tell.

So here he is, looking like a pinched version of a youthful Seb Coe, perched on a seat in Numis’s City head office at Cheapside, and reluctantly helping me to unpick his idiosyncratic style.

He insists, for instance, that all his 100-plus employees actually buy a stake in his business — share options are not on offer. “I look for people who care about Numis,” he says, “and want to own a share of it.”

But what if they cannot afford to?

He giggles. “If they cannot afford it, I would hope they would borrow money to buy in, or I would help them with a loan.”

In hock to the boss? Well, he can probably spare the cash. Hemsley, a pig farmer’s son born in Rutland, now has 600 acres of Dorset under his belt and is taking flying lessons with an eye to getting his own plane.

Yet he loves the traditional things in life — tightly waisted English suits, John Buchan novels and fox hunting, to name but three. When he is not being the thrusting, self-made entrepreneur, he is every inch the upper-crust toff of City legend.

Such unpredictability gives him the element of surprise. Last year he was rumoured to have turned down a takeover approach for Numis from Landsbanki, Iceland’s second-biggest bank, that would have valued his 18% stake at about £25m.

He didn’t sell, he shrugs, not because he is very rich already, but simply because he wants to keep building the business. “And by the way, we have never commented on the offer but, yes, we did receive an approach. You can assume it was an offer for the whole company.”

What happened to the bidder? “They returned to their cod-infested shores.”

He giggles again, before making a face, realising that he shouldn’t have let that one slip out. But that’s what’s interesting about Hemsley. He really does seem to be a bundle of contradictions — acerbic wit fighting City-style reticence, old-school demeanour butting up against fiercely modern, meritocratic drive.

It makes him difficult to read for some, who can’t quite square the fox-hunting grandee who cut his teeth at Lloyd’s of London with the aggressive business builder who regularly puts in 14-hour days. Or the fact that he turned down a takeover bid for his firm, when at least one friend tells me he is always moaning in private that he should sell out.

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