'A magician never reveals their secrets' is an adage known the world over.

But the secrets behind one magic trick, pioneered by a Norwich man, could be yours for the taking in a competition which requires one thing of contestants: an act of kindness to a stranger.

Alex Walton, who has run previous campaigns in Norwich to promote random acts of kindness, is supporting a campaign to give away a 1915 gold sovereign and the details of a trick it was used in, devised by hobbyist magician Arthur Boardman.

Mr Boardman, who worked with a number of magicians in the early 20th century, showed his trick involving five sovereign coins to three top magic men of the time, including Houdini and Harry Kellar.

The trick, known as 'the Sovereign', involved making the coins disappear, but Mr Walton, from Old Catton, said: 'In magical circles it was never discovered how it was done.'

Now a member of the public has the chance to win one of the sovereign coins used in the trick, as well as documents relating to how the act is performed – by completing a random act of kindness.

Mr Walton, who lives in Old Catton, said the challenge was inspired by the trick's creator.

'Arthur worked with some of the most famous magicians in the world and after he retired he used to do a lot of good deeds,' he said.

'We are looking for people to do a good deed, a random act of kindness for a stranger. There will be one winner who will take away the gold coin and the documents showing the provenance of the trick.'

This idea also struck a chord with Mr Walton. He runs a Twitter group called @findmystory which promotes random acts of kindness, and over the past few winters he has placed hundreds of envelopes in cities around the UK – including Norwich – to spread messages of hope and festive cheer to strangers.

As with these previous campaigns, Mr Walton will be using social media to promote the challenge to secure the secret of the sovereign trick.

'What we are trying to achieve with giving the coin away is to build the momentum around random acts of kindness as much as we can,' he said. 'I am not running this opportunity but I am supporting it.'

Find out more at www.thesovereign1915.com.