Dickens gives us (and Pip for that matter) great hope in a relationship between Pip and Estella. Pip receives a letter that says Estella is coming to town and he is to meet her. This makes readers believe that for all this time while we have watched Estella mock and abuse Pip, there just may be that glimmer of hope for him with her. Now, it feels to the reader like a relationship for them is not only possible but probable. While readers get anxious right along with Pip, Dickens drives the story away from Estella.
Wemmick comes along and takes Pip to Newgate Prison. A prison is an ironic place to go considering what Estella's treatment to Pip over the years has done. This negative experience might make readers wonder, is this meeting between Pip and Estella going to be any different, or is Pip yet again bound to the life from which he began. The prison experience is also a connection to who he finds out is his benefactor as well as to what we learn about his connection to a convict in the very beginning.
Finally, the chapter ends with an ominous question:
What was the nameless shadow which again in that one instant had passed?
A shadow could be so many things. It could refer to the past or the future. It could refer to a bad experience. It is unnamed, so once again we are guessing. But, it is a clue and you will be able to put it all together in the end!
Chapter XXXII of Great Expectations is one in which Charles Dickens the social reformer gives his voice to the character Wemmick who walks among the condemned as a man walks around in his garden. Here are men who have been condemned by society although some of them possess sterling qualities. The experience of moving about with Wemmick in the prison awakes memories in Pip of his own guilt as well as of the "man in coarse gray" that he met on the marshes. Thus, again the motif of guilt arises in Pip as he connects to these prisoners and recalls his own guilt.
I consumed the whole time in thinking how strange it was that I should be encompassed by all this taint of prison and crime; that, in my childhood out on our lonely marshes on a winter evening I should have first encountered it; that, it should have reappeared on two occasions, starting out like a stain that was faded but not gone; that, it should in this new way pervade my fortune and advancement.
Clearly, there is foreshadowing of the reappearance of this convict in gray who was shivering on the marshes. This is the "nameless shadow" that passes before Pip.
Suspense is also created as readers wonder what has become of Pip's convict and if he will return, just as they wonder what the relationship of Pip and Estella will be now that she has written him to pick up her at the coach.