I was lucky enough to catch Capturing Mary on cable, a BBC movie made in 2007. The lead is a writer who, in her seventies, goes back to the (now empty) mansion where 40 odd years ago something changed forever her way of viewing life. As she tells the story to the caretaker, the scenes she brings back from the past come to life. At the end, she goes to a park, sits on a bench, cries the hell out, becomes very still and, without a word, "talks" to the camera with unbelievable eloquence. Not exactly the kind of thing any actress can handle. That must have been why they decided not to cast an actress. They cast a monster, a sacred one. A mythical creature, like those of the legends of old that ended up having a constellation named after them. They cast Maggie Smith.
Maggie Smith is one of the four or five women in the entire history of films who made it crystal clear that, just like saints and poets, some actors are destined to help whoever is journeying to the light not to go astray.