You may have thought your eyes were playing tricks on you - was that really a photo of Camilla trying on a wedding dress?
The artist Alison Jackson caused controversy with her photographs of celebrity look-alikes in unlikely situations - such as Camilla trying on a wedding dress, Osama Bin Laden playing backgammon or Margaret Thatcher comforting Jeffrey Archer in prison.
Alison Jackson joins Martha to talk about her TV project, Double Take.