Huntley and Palmers: Biscuit tin sex secrets revealed
An illustrator has been explaining how he sneaked "naughty" images on to biscuit tins of a leading manufacturer, which were distributed world-wide.
Mick Hill, from Whistable, Kent illustrated the tins, now kept at Reading Museum, for Berkshire-based Huntley and Palmers in the 1970s.
The artist who has been "keeping a low profile" since his prank was discovered, has been showing the BBC some of his handiwork,
Video journalist: Adam Paylor