I've found many shows after Edge of Darkness seen to have a similar vibe, which suggests influence. For example I recently watched the first season of Homeland.
Can anyone identify shows before Edge of Darkness that might have influenced its creation.
Callan would definitely be one... and then... really the only other thing that comes to mind is an old horror mini-serial for kids called Children of the Stones, simply because of the bizarre and eery vibe, and the pronounced Britishness. Children of the Stones has nothing to do with nuclear power or political shenanigans though, it just has a similarly surreal yet grounded feel to it, at least at the start.
That's not a very good suggestion I admit.
Maybe something like the (long suppressed) BBC documentary "The War Game"?
Alan Bleasdale's G.B.H. has a few elements in common with EoD (callous and out of control security services infiltrating and using the unions and the left wing for their own ends, a large amount of black comedy, some larger than life characters) but without the hints at international deep politics, or the supernatural and occult elements that make Edge of Darkness so unique and strange. Of course G.B.H. came later.
Oh yeah, you've got to love A Very British Coup! Still haven't seen it all the way through yet though.
Children of the Stones only has a very vague similarity in terms of atmosphere, and it might just be because I watched both series (recently) at around the same time. The older film quality and the big brick-like technology used is kind of the same. A bit. Maybe it's just the wailing music that has fused the two in my mind. .
Especially Jedburgh's cowboy character--he played it a bit over the top garrulous, which is perfect for Jedburgh. But did seem to draw a bit from "Fail Safe."
Also, even though the topic is not the same as EoD, the original '70s production of "Bouquet of Barbed Wire" would certainly have been a groundbreaker in this kind of bleak portrayal of life.