P.D. James' Death Comes to Pemberly- Pitiful Plagarism

P.D. James is a British author famous for her mystery & crime solving novels.  James has received numerous Silver Dagger Awards for her mysteries.  She is an Offficer of the Order of the British Empire and Life Peer in the House of Lords since 1991.  As an American, I've surmised these honors give entitlement to plagiarize & diminish the great works of a truly great British author, Jane Austen.  I am unabashedly a Austen fan and perhaps this makes me disdainful of the improvised future between Mr. & Mrs. Darcy which is mired in a murky, melodramatic murder mystery.  Of course, the culprit appears to be Mr. Wickham who married Elizabeth's sister Lydia but remains barred from Pemberly.  Lydia turns up on a stormy night at Pemberly in hysteria.  Lydia maniacally insists Darcy & the Colonel  search the grounds of the estate for her husband whom she fears has been killed.  Wickham is discovered kneeling over the bloody body of his companion Denny, blaming himself for his friend's death.  A trial ensues with Wickham as the defendant.   The outcome for Wickham looks as bleak as the dark, wintery countryside.   Alas, there are plenty of warming fires along with a burning love between Elizabeth & her husband Fitzwilliam Darcy;his having married beneath his social class.  Therein lies the strength of the novel, social stratas, decorum and the daily "Downton Abbey" lifestyle for both the aristocracy & the servants.  The legal conventions of the time are also of interest. But, DEATH COMES to PEMBERLY is a flagrant rip-off of Austen's beloved characters in a who done it which does nothing for me.