In Chapter 48 further secrets are unearthed through the realisation by Pip that Molly, the housekeeper of Jaggers, who is obviously under his power, is Estella's mother. It is important to note how carefully this is inserted into the text. At various stages previous to this Chapter (Chapters 29, 32, 33) Pip's meeting with Estella has been marred with a darkness or a shadow that comes between them. It is know that we realise what that shadow is.
After the dinner at the house of Jaggers, Wemmick walks home with Pip and relates the background of Molly. Jaggers managed to acquit her of a murder against the odds. She had been married to a tramp and had been charged with strangling another woman in a fit of jealousy. There were also unconfirmed rumours that she had committed infanticide, killling her little daughter.
This chapter represents yet another link between the criminal underworld and Satis House by showing how Estella's mother was a murdress. A key theme that runs throughout this novel is how Great Expectations are inextricably linked to illegal, criminal elements, highlighting that one person's gain is always at the expense of another's loss. It also lays the path for the revelation of who Estella's father is, now that we know who her mother is.