Chapter 52

1)  Pip concludes his arrangements for Herbert's partnership.  He concludes that this was the only good thing he had done.  Is this true ?

A mysterious and threatening letter arrives. 

2) This is turning into a sort of mystery novel, full of intrigue...who do you think sent Pip the letter that brought him back home?
Why doesn't Pip tell anyone? Is this part of his character? Or a plot device by Dickens?