If you read the book you Will not Like The 2016 Moonstone TV series.

You will definitely be disappointed (1) if you have read the original novel or (2) were lucky enough to watch or have the superb 1997 TV move -also produced by the BBC during an era when it was its best in producing classical TV dramas. Recently, besides the 2016 remake of The Moonstone there have been equally poor quality remakes of the 1983 Jamaica Inn TV movie and a bungled screen version of War and Peace, which does not stand up at all to the now technically-remastered Russian epic of the 1960s
In making my judgement first the novel itself should be the standard of how badly the 2016 version is as a TV series (215 minutes) compared with the excellent BBC 1997 TV movie (120 minutes). Here are some of my specific dislikes of the 2016 version.
Ghastly miscasting of most of the lead parts. The BBC on its website admitted that it has deliberately trashed the novel’s mid-Victorian English and replaced it by today’s garbled geek version of the semi-literate. They argued that the purpose was to allow the present generation to understand it!
The was also some unnecessary recasting of the the 74-years old character admirably acted by Peter Vaughan of Gabriel Betteredge, the butler , substituted by Leo Wringer, a forty-something black man with a Caribbean accent who would have been better in Uncle Tom’s cabin or in Twelve Years as a Slave (there is also what appeared to be a Philippine housemaid). Such exotic domestic servants in the mid-Victorian era might have been fairly common in the big cities such as London or Bristol but the pool of local labour in peripheral rural areas and the further provinces meant domestic servants were not all scare and were cheap back in those days .They are all pale-faced Yorkshire people in the novel as they were in the 1997 TV move. The black man as butler is a rather feeble attempt to seem politically correct.
One would think that given the extra 95 minutes available to the producers of the 2016 version a lot more could have been accomplished. Instead, while the 1997 TV movie did have to delicately cut some corners from the novel due to time limitations the effort was bespoke tailoring, whereas the producers of the 2016 version decided to use ready-made material. One would expect better cinematography for the 2016 version than what was available twenty years ago but the 1997 version succeeded whereas the recent one failed dismally.