When they agreed to act as frontmen in 1976, the Bolsoms had just passed the pinnacle of their business careers. They may have been looking for opportunities. They may have been tempted by the offer of a nightclub in one of the Barclays’ hotels. They may have simply been tempted by the idea of earning a handsome sum without having to do any work.

Leslie, who was then 59, and Harold, who was two years younger, were serial entrepreneurs who had created many hundreds of jobs. Like the Barclays, the brothers were inseparable in business. They shared almost all their ventures, which were split 50/50 between them. They cut their teeth at Champion Electric Corporation, which made radios and electrical cookers. It had been founded in 1939 by their father, Monty, the son of a Polish immigrant, who had started out as a bootmaker in London’s East End and taught himself to be a radio engineer. Both Monty and his younger son were inventors with patents to their name. The business thrived, thanks in part to clever marketing and stylish products.

In 1957 the Bolsoms sold Champion and, although the brothers had made enough money never to have to work again, they soon obtained the British distribution rights for Clarion portable tape-recorders. Back then portability was a new concept, and they set up a shop in west London to sell imported gadgets. However, as rival products came to market, the business failed to thrive.

The Bolsoms’ most eye-catching deal was getting the Carmen Curler franchises for Britain and the Netherlands. They met Arne Bybjerg Pedersen, the curler’s co-inventor, on a trip to Denmark in 1964. At the time he was struggling to get the business going. The turning point was the Bolsoms’ order for 500 curlers. When an institutional investor bought a 25% share of the company in 1969, the business was valued at £43.4m in today’s money*. The Bolsoms gradually reduced their initial 50% stake, before selling out in 1974. By then, the business had sales of £98.2m and employed over 275 people.

The Economist has not been able to establish how the Bolsoms met the Barclays. The first time they have any provable connection is when Trenport offers to buy the Barclays’ debt.

However, the two pairs of brothers are likely to have come across each other in west London. In the late 1950s the Bolsoms moved to Bayswater, where they spent the rest of their lives. That was also the site of their next venture, a 200-room hotel called Leinster Towers, which opened in 1962. The Bolsoms owned it for seven years before selling it in early 1969 to a large British brewer at a pre-tax profit of £3.8m in today’s money.

The Barclays opened what we think was their first-ever hotel in the area in 1964, only streets away from Leinster Towers, before opening two more hotels in the 1960s. The Bolsoms also may have bought property through a Barclays-owned Bayswater estate agency.

After the Bolsoms cut their ties with the Barclays, when they were bought out of Le Privé nightclub, the Bolsoms’ touch deserted them. Purchases of a car dealership and an audio-equipment business ended in failure. Beauty and personal-care businesses flopped, leaving a trail of unpaid debts. Several of their companies went into insolvent liquidation in the mid-1980s.

If the Bolsoms had been behind the Trenport deal, as they pretended, they would have made something like £40m from dividends and the sale of shares to Russet. This money was offshore. However, there is no evidence that they brought money home or that they kept a secret stash in Jersey.

Our investigations show that they may have lost up to £1m on companies they bought. In all the filings we have examined of the Bolsoms’ companies, we found no trace of any offshore entities holding shares. The money the Bolsoms lost in the 1980s mainly involved the depletion of their stock of wealth before 1976, as their companies began to fail.

When the key family company went bust in 1989, the biggest creditor was the “Inland Revenue Enforcement Office”. The nadir came six years later, when Leslie, who had always played fast and loose with his taxes, was made personally bankrupt by the tax authorities. Records show that his trustee in bankruptcy found very few assets.

Leslie died in 2006, Harold in 2008. Probate records show that the gross value of Leslie’s estate was £890,170 and his brother’s was £1,023,055. An executor of one brother’s estate told us that: “His estate was straightforward, comprising mainly interests in property. To the best of my recollection, he held no assets offshore.” If the Bolsoms had really been Trenport’s owners they would have emerged from the deal vastly richer. In fact, their fortunes declined. ■

*The figures in this article have been converted to December 2023 prices, using a retail-price index.

Read the full investigation here.