@Roussette
I do have to say...having a lighting engineer father will do sod all landing you a major part in a TV series!. I can't imagine you can be serious with that assertion
Her first husband, a film producer, was said to have boosted her film career because of his job and there is no doubt MM was in films he was producing which does lead credibility to that.
Like Zara, I think MM had an ability to act because she would not have continued to be able to work in that field otherwise. However, by no stretch of the imagination (unless you are part of the Sussex Squad) has she ever been an A list actress.