'A good story with a real twist of an ending'

 Having been found in a hospital by her parents, Max and Laura, after her disappearance several years ago, Emma's homecoming should have been an event of unalloyed happiness.  However there is something strange about the situation.

Emma's memory is damaged, which could be why there is much she does not recognize, much that does not quite fit: but then why does she appear familiar with certain Russian phrases?  Why has she such a horror of a harmless silver bell?  Of a portrait on the wall?  Of knives?

What lies behind the odd behaviour of the new 'hired man'?  
What is the significance of Max and Laura's somewhat ambivalent attitude towards their daughter?

Is she, in fact, their daughter?