In this version of Death Comes to Pemberley, Darcy's grandfather has actually ruined the family, and they've had to stoop to cooking meth to save Pemberley and restore the family's fortunes. And, of course, Captain Denny is killed because he gets on the wrong end of a drug deal gone bad, and Wickham gets railroaded for it and is hanged. But the social ruination for the Darcys due to the link to the murder scandal only serves to grant them extra "street cred" for their underworld drug empire, as well as scare away any potential competition drug cartels and deadbeat clients.
And they all lived happily ever after, or at least until the meth lab in the cottage blew up, and Sir Selwyn Hardcastle had to come bust them.
It's here: the combination of Pride and Prejudice and Breaking Bad you've been demanding!
It's Meth Comes to Pemberley: coming soon!