From NetFlix:

When police detective Ron Craven (Bob Peck) witnesses the murder of his environmental activist daughter (Joanne Whalley), he vows to track down her killer. Little does he know, however, that the trail will lead straight to the heart of Britain’s nuclear power industry. The suspense ratchets ever upward in this award-winning BBC miniseries, as Craven finds himself smack in the middle of a top secret government project. Joe Don Baker co-stars.

This “Edge of Darkness” is the original 6-episode British TV series as opposed to the 2010 Mel Gibson remake. As such it proceeds at an unhurried calm pace. Alongside the conspiracy plot there are the psychological after effects of Craven’s having seen his daughter gunned down. There is some violence, but no gore. And of course the villains are cool and calculating.

According to the Wikipedia article, this series as been acclaimed as one of the best and most influential pieces of British television drama ever made. Be prepared for pessimism and a bit of magical realism.

As an extra, the very appropriate “Edge of Darkness” electric guitar theme that runs throughout is by Eric Clapton.