A US millionaire who became famous after leaving a trail of hidden cash envelopes on the streets of San Francisco has brought his HiddenCash treasure hunt to the UK.
Property investor Jason Buzi hid tens of thousands of dollars around the US and tweeted cryptic clues to help people find the cash prizes.
Buzi, who posts clues from his @HiddenCash Twitter account, has now hidden 20 envelopes, each containing around £100, around London.
The entrepreneur has already posted a series of clues to point treasure hunters in the direction of the hidden prizes.
The first clue was "Large space where green meets blue. Saturday neither early nor late." This was followed by: "An unincorporated community in Northern California shares its name with our London drop spot."
Speaking on Sky News, Buzi also gave the following clue: "A popular children's story takes place here."
Buzi said he is thinking about expanding the game to the rest of the UK and taking it to other European capitals such as Paris and Madrid. In the US, similar treasure hunts have taken place in Los Angeles, New York, Houston and Chicago.
Buzi, who says he is one of the US's richest 1%, made his fortune buying and selling homes.
Earlier this month, Buzi was unmasked as the individual behind the initiative after a voice expert was used to identify him after he gave an anonymous interview to the news programme Inside Edition.
"I really am just trying to give back," he told website The Bold Italic. "I would love to have more join me to give back more."
"I wasn't born wealthy. Many people I know have done better than me and they're not doing anything to give back."
Buzi said five other benefactors have started donating to the social media charity venture, and having been unmasked, he will act as their spokesman.