A common enough story - during appraisal it's discovered that 1 painting has been concealing another. In this instance a portrait of Sir Alfred Munnings reading a book, hidden (it is speculated) for fears that a jealous husband would not be so impressed....
Read full article here: http://www.telegraph.co.uk/culture/art/art-news/6209440/Secret-portrait-of-British-artist-hidden-behind-another-canvas-by-admirer.htmlÂ