Luna is the only one to mourn the death of her grandfather Old Man Moon - the rest of her family couldn’t be happier to see the back of the bad-tempered old miser. But as they celebrate his demise with a giddy jig, Aunt Summer vanishes … only to reappear as a painting. While Luna is convinced her grandfather has kept his word to haunt them from beyond the grave, Skeleton Keys is certain that this is the work of an unimaginary. Can he get to the bottom of the mystery before the whole of Luna’s family disappears?