What If the Earth Itself Really Is Alive? Should We, Can We Subdue the Earth Within Us? I read the novel before watching the movie, and both are excellent, with the book being slightly superior to the film because it can weave in the innuendo, nuance, and Freudian symbolism more effectively than the film. The movie is quite faithful to the book, although the film gives comparatively more attention to the Sara Waybourne character and less attention to Irma Leopold.
I highly recommend considering the rock a character - perhaps the most important character - in this film; I ask you to consider that the rock is not a static, dumb object as we would interpret it from our modern, materialistic viewpoint. Rather, by accepting a more aboriginal, animist interpretation of the rock as a living being, the viewer gets in tune with a different understanding of the underlying reality of things which should make it easier to comprehend and appreciate this film. In connection, it also may be helpful to remember Australia is a continent which was stolen away from the native inhabitants by Europeans, who fancied their culture more advanced, civilized and reality-based than the aboriginal culture; this European conquest has lasted for a tiny blip of a second when compared to how long the natives have lived there. Also, one of the cultural hallmarks of Christian Europe was the (at least partial) sublimation of sexuality in order to fuel presumably higher goals, for example, art such as this movie.
On one level, "Picnic at Hanging Rock" is about the suffocating sexual repression of the Victorian age. The older students at this girls boarding school are just entering into that golden period of 16 to 24 years old, that fleeting period when humans are at their most vigorous, fertile, robust, sensual and beautiful. This makes the repression all the more crucial. There are clues sprinkled into the movie to help the viewer make up their own mind as to what happens, but you have to pay careful attention: this is not a Hollywood style movie where you're hit over the head with plot developments or character motivations in high relief, nor is every question that arises clearly answered in a reassuring, formulaic way. If you like easy answers, forget this movie and watch a Hollywood flick.
Most of the cast is solidly good. Dominic Guard as Michael Fitzhubert and Anne Lambert as Miranda are perfect choices for their facial features, physical build, and mannerisms. I would have cast the character of Irma Leopold differently. In the book, she is described repeatedly as stunningly beautiful, and although the actress who plays her in the movie is quite attractive, she is not stunningly beautiful.
One of the girls quotes Poe: "All that we see or seem is but a dream within a dream." Another girl gushes, "The rock has been waiting thousands of years, just for us!" Ultimately this film is relevant to everyone alive on planet earth, because on this second level, "Picnic at Hanging Rock" is about that biggest mystery of all - being and nothingness.