Josh Adley and Natasha Langleben had no idea they were going to be surprised by a secret millionaire on an episode of Channel 5’s Do The Right Thing.

The Jewish siblings, who are founders of the social enterprise charity Linkey were left speechless when presenters Ruth and Eamonn Holmes revealed that a wealthy benefactor wanted to give them £15,000.

As part of the show, broadcast on Thursday evening, “Joe the reporter” came to their house to film them packing items for the homeless, which they drop off at shelters around London.

Mr Adley, who set up the initiative with another sibling pair, said they thought they were going to be part of a feature on people helping their communities.

However at the end of the show it was revealed that Joe was in fact an undercover multi-millionaire who wanted to help fund Linkey.

Mr Adley, 28, said: “We were in the studio with Ruth and Eamonn when they came clean to us. It was a massive surprise. We were speechless we didn’t expect it at all. We just thought we were there to tell them about Linkey and what we are doing to help.”

He said the money would allow the charity to continue its monthly drop-off to homeless shelters of food and clothing.

Mr Adley has previously said the charity needed a van to transport the supplies.

He and his sister were “blown away” when Joe presented them with a van to use for a year, with their logo painted on it.

The two pairs of siblings were inspired to set up the charity after helping the homeless over the Christmas period.

Last December Mr Adley, a member of Alyth Synagogue, in North-West London, and his wife Rebecca encountered a homeless man in the street while they were enjoying a night out.

Mr Adley said: “The man asked if we knew of a shelter that would be open, but we didn’t.

“Upon asking around and looking online it seemed nothing was open until the morning unless you had a referral.

“We bought the man a meal and chatted for a while. But later that night I wanted to help more so I filled my car with warm clothing and drove back to try to find him, but I couldn’t see him.”

Mr Adley said he could not stop thinking about what might have happened to the man.

“I decided to set up a day where we would gather as much warm clothing and toiletries as possible to take to homeless shelters and rough sleepers between Christmas and New Year,” he said.

“Originally it was only going to be a one-off day of dropping off.

“However having spoken to the shelters they said they get quite a lot given to them over Christmas and it was January to March when they were most in need.”

Since setting up, Linkey has collected more £20,000 worth of items for the homeless.