From the blurb:
London, 1955. Three bodies are found in a house - but when the police search for the murder weapon, vital evidence is destroyed. One of the victims is former society beauty Georgina Gresham, prime suspect in the notorious murder of her husband, James, almost thirty years earlier. Beside her lie the bodies of her brother Edmund and housekeeper Ada.
But there is a link with the past. In the 1890s, in a beautiful garden, three children played together. Their lives were secure, their future certain - until the youngest child was found with fatal head injuries...

I'm not sure where I got this from, but it sounds interesting and I hope to find time to read it before passing it along.

Releasing at the Unconvention.