The letter that landed on the doormat of a London home on a cold, wet January morning seemed intriguing, enticing and potentially life-changing.

Personally addressed, it appeared to come from the Causeway Bay home of a Chinese banking executive based in Hong Kong and offered an illicit opportunity to share an unclaimed, $12.2 million fortune.

Wei Dingxiang, as he introduced himself, claimed to be a director of private banking with the Industrial and Commercial Bank of China (ICBC) handling the estate of a westerner called Jeffrey who had invested his money with the bank.

When Jeffrey was in the process of liquidating his assets, however, he had died in an accident in the Chinese mainland, leaving no will and with no next of kin, meaning his fortune would revert to the Chinese state unless it was claimed.

Now came the clever bit.  Wei was writing to the addressee because he shared the same, rather unusual family surname as Jeffrey — creating a unique opportunity for a piece of illicit business that could make both banker and addressee wealthy. For safety’s sake, he had asked a friend visiting the UK to post the letter on his behalf.

“What I propose is that since I have exclusive access to the file, you will be made the beneficiary of these funds,” Wei wrote. “Through my covert efforts, my bank will contact you informing (you) that money has been assigned to you.

“I know this might be a bit heavy for you but please trust me on this. For your troubles I propose that we split the money in half. In banking circles this happens every time. The other option is that the money will revert back to the state. Nobody is getting hurt; this is a lifetime opportunity for us.”

Wei appeared sincere, articulate and almost poetic in his furtive appeal. “Please, note I am a family man; I have a wife and children. I send you this mail not without a measure of fear as to the consequences, but I know that nothing ventured is nothing gained and that success and riches never come easy or on a platter of gold.”

A platter of gold, nevertheless, is what appears to be on offer, so the China Daily decided to investigate the source of the letter in Hong Kong and to communicate with Wei to see how sincere and genuine he really was.

In this, we had an advantage over the recipient of the letter in London: We could actually visit the address in the letter and ask Wei to meet us in Hong Kong. And the more we communicated with Wei and the closer we got to a meeting, the more his story fell apart.

Our first port of call was the address on the top of the letter: 36 Haven Court, Leighton Road. A Causeway Bay address which — to an outsider with a passing knowledge of Hong Kong — might sound a likely location for a married private banker to have a comfortable apartment.

In fact, we discovered, Haven Court is a narrow corridor of shops beneath an ageing block of low-rent flats and offices — and number 36 is a derelict one-room shop. “It’s been empty for some time and it’s used for storage these days,” a neighboring shop owner told us. “There’s definitely no Mr Wei there.”

Then there was the phone number — (852) 800 966 124. A recipient in London would not recognise it but although the international code is correct, the number itself is not a regular Hong Kong number and looks more like a toll-free line.

In fact, Hong Kong numbers starting with 800 are forwarding numbers that can be bought for around $15 a month and which enable calls to be patched straight through to overseas numbers. Every call we made to the number was answered with a brief answerphone message from an undistinguishable flat male voice.

Finally, there was the email address, on an untraceable email account. Posing as the London recipient, we emailed Wei to express an interest in the illicit venture. He replied with a long email complete with a copy of his passport, an ICBC staff card and a utilities bill.

In return he requested seemingly innocuous particulars of the recipient such as name, address, email, company name, fax and phone numbers and date of birth, allegedly to begin the process of the money transfer.

Effusive and conspiratorial in tone, the letter written in surprisingly good English said: “In everything one does with another there must be a meeting of minds … As we say in Cantonese ‘Thoroughness is what is needed here’.”

We then broke the good news to Wei. By chance, the recipient has been sent to Hong Kong for business and would like to meet in person to take the venture forward. Suddenly Wei becomes a little elusive.

He promises repeatedly to meet while asking for our personal details to be emailed first as “time is of essence” and cautioning: “A one-off meeting is not going to give the guarantee that is required.”

In subsequent emails, believing the window of opportunity for a Hong Kong meeting is limited by the length of the victim’s visit, he repeatedly failed to commit to a meeting, saying first he was on business in China, then that he got his times mixed up, and finally going silent. The emails are mostly sent in the middle of the night Hong Kong time.

The reality is, of course, that Wei never existed in the first place and could never make the meeting in Hong Kong because his emails were being sent from overseas — possibly from London but just as possibly a city in Africa and in particular Nigeria where many such scams originate.

The fraud works by preying on people’s greed and gullibility and gradually draws victims in through exchanges of emails. Then, at a later stage in the supposed transfer, unexpected legal fees or other emergencies crop up requiring up-front payments amounting to thousands of US dollars.

We contacted Doris Lee of the Legal and Compliance Department of ICBC (Asia) in Hong Kong and forwarded the documents and correspondence from Wei to her.

“Mr Wei is not an employee of ICBC in Hong Kong,” she told us, adding that the matter had been referred to ICBC’s head office in Beijing for investigation. ICBC had not come across a fraud of this kind involving the bank previously, Lee said.

In fact, the case of Wei is a clever variant on an existing scam known as the advance fee scam. One element that sets it apart are that the letter and emails are well-written and do not bear the grammar and spelling mistakes which usually make this type of fraud easy to spot.

It is also addressed to specific, named recipients when it is more usual for them fraudsters to spam multiple addresses and address the letter simply as “Dear Friend” — suggesting the scammer had researched names and addresses from electoral records.

However, if you put the name Wei Dingxiang into a Google search and the name also crops on a website called www.hotscams.com in a warning from someone also with an unusual surname.

“My daughter received a letter from Wei Dingxiang, director of the Industrial and Commercial Bank of China ICBC based in HK, stating he could recover a deceased relation’s bank deposit and share the proceeds with him. What rubbish but so sincere. Please avoid!” the message says.

Letters containing almost identical content also appear on other scam warning websites but with names such as Xiang Li, Soo Won-lee and Yipeng Li who claim to be senior employees of the Agricultural Bank of China, the Nanyang Commercial Bank and the HuaXia Bank.

Like Wei’s letter they all ask the recipient to keep the contents of the letter confidential and, significantly, repeat word for word his expression about success and riches never coming easy or on a platter of gold.

Details of the fraud were passed to the police by China Daily. A Hong Kong Police spokesman said it bore the hallmarks of an advance fee fraud.

This usually involves a targeted victim receiving unsolicited email or mail from the fraudster whose ultimate aim is to cheat people into remitting funds that allegedly represent administrative, legal, tax-related fees into bank accounts set up by fraudsters.

“Alternatively, fraudsters may use different excuses to get people to provide their personal information, which may be used in furtherance of additional criminal activities in future. The most common excuses are claims that they are the beneficiary of an inheritance or winner of a lottery,” said the statement.

The fraudsters may use different methods such as email, fax, telephone and even SMS to contact potential victims.

The advance fee fraud is also known as the 419 scam, which is named after the section of the law which outlaws it in Nigeria where the practice originated and still proliferates.

Hong Kong police warned the public to be cautious of unsolicited emails, fax, telephone calls or SMS, especially so when they contain an offer which sounds too good to be true.

“Do not respond to unsolicited emails which ask you for personal details or transfer money and consider using an email "spam" filter,” said the statement. “If in doubt, contact or refer the case to the police.”

A police officer familiar with email frauds said: “The Mr Wei letter seems like a clever version of an old fraud.

“The people behind it may never have set foot in Hong Kong. But they are playing on Hong Kong’s reputation as a city where huge sums of money are handled, and China’s reputation in the west as a place where there is both great wealth and a certain level of official corruption.”