Definitely the groovy face of horror at that time, putting the 'super' into supernatural; in the years just before "Tales..." he was in Dr Jekyll and Sister Hyde, Horror of Frankenstein, Taste the Blood of Dracula and Lust for a Vampire.
I wouldn't think of him as a horror star either. But he was in a lot of Hammer films - and was seen by the company as being their main face as they went into the seventies; and the person to take over from Peter Cushing and Christopher Lee.