Well, the way John Yeagar "appreciated" Maggie Collins' hairbrush in one scene I don't think I'll ever forget was certainly "adult"--I also love Yeagar's scene with AngelExis (which I think is in the same show).
In some ways, AngelExis' attempts at Witchcraft were more realistic than the "SuperWitch" stuff Angelique was pulling in our time--AngelExis wasn't really in control of her own powers and kept over shooting the mark, which I thought leant more tension and suspense to the way in which the Witchy stuff was used in this storyline.
And then, with the murder mystery we get a combination of the old Agatha Christie country house mystery genre, which is another perennial favorite--yep, PT 1970 really was "the stuff"!
G.