Files released last week by MI5 reveal how a publisher smuggled diamonds hidden in chocolates into the UK.

Francis Maynell, later knighted, was director of the Daily Herald and editor of The Tablet between the wars, but he came to the attention of the security services as an active peace campaigner during the First World War.

Meynell led the ‘Guild of the Pope’s Peace’, which was viewed by British officials as an extremely suspicious organisation, in part because of its lobbying for peace ‘at any cost’, but also because its Catholic background led to suspicions that it was pro-German.

The MI5 file on Meynell describes him as ‘an extreme socialist’ and includes allegations that he was involved in propaganda designed to undermine the morale of the British army.

Extreme socialism had an unlikely encounter with extreme glamour however, when in 1920 Meynell was on a trip to Scandanavia and he was given £40,000 worth of gems by Lenin’s Soviet regime. He was tasked with smuggling the diamonds into the UK in order to help keep the radical Daily Herald afloat.

It’s not clear whether he took the method from any known spymaster’s playbook or whether he came up with it himself, but he bought a box of chocolates, removed the cream contents, hid the ‘Bolshevik diamonds’ inside the chocolates and replaced the silver wrapping to cover his tracks.

Once he was satisfied with his handiwork he simply posted the chocolates to himself back in the UK.

It’s thought that the diamonds had been looted, along with pearls, by the Bolsheviks from Tsar Nicolas II.