The Avengers was one of my favorite shows when I was a kid. Mrs Peel was smoking hot!
The big secret of the show was that Mrs. Peel was the best screen depiction of a dominatrix. Brits have long been fascinated by them, which meant a lot of adult men were riveted to the screen as well.
Looking at The Avengers again, you can catch a lot of the subtle hints about this from her attitude and facial expressions. Some very fine acting.