Dr. Bendor Grosvenor and Jacky Klein visit the Ulster Museum to investigate what have long been disregarded as low-value copies of works by Flemish artist, Peter Breughel the Younger.

They also visit the Northern Ireland Assembly at Stormont, in which a controversial painting once slashed with a knife is now kept in a room away from public view. The subject is believed to be William III and the Pope - these two characters in one picture would be guaranteed to rouse the passions on both sides of the sectarian divide. But has the painting been a case of mistaken identity? Bendor and Jacky investigate.

Haddo House is one of Britain's most northerly stately homes. Tucked away in the wilds of Aberdeenshire, it has been home to Prime Ministers and earls - but is it also home to some of Scotland's greatest lost paintings?

Nearby, in the storerooms of the Montrose Museum, lies a mystery painting with a giant hole in it. The portrait shows Richard Mead, the patron of one of Scotland's most celebrated painters, Allan Ramsay. According to the history books, the painting is a copy of a painting in the National Portrait Gallery in London. But has there been an unfortunate mix-up, and is the painting in London in fact the pretender?

The Swansea museum store contains everything from a stuffed pigeon to a police car, but can Bendor and Jacky reveal a multi-million pound lost masterpiece that will not only become a jewel of Swansea museum's collection, but also re-write art history?

Also in this episode, a rare appearance at the museum of a giant painting of local coal miners prompts Jacky to re-examine the life of the man who painted them, the renowned Polish artist Josef Herman. She tracks down those who remember him in South Wales.