This is one of the best films ever made on the issue of hypnosis, its use and misuse, life before birth and after death and reincarnation, all tremendously difficult issues and almost impossible to discuss, least of all to come to definite terms with, except by hard trial and error in bold experiments, which this film and story is all about.
The one responsible for the book, a tremendous bestseller in its day, a certain Morey Bernstein, has no interest whatsoever and doubts everything, rejecting all psychic business as mumbo jumbo, until a hypnotic experiment in his presence is too authentic to be rejected, which propels him into studying the subject. By pure personal interest he trains himself into an amateur hypnotist and achieves results as such and finds a very susceptible guinea pig for his risky ventures into the unconscious in a young mother Ruth Simmons, whose husband isn't happy about it. With her under hypnosis the amateur hypnotist stumbles into past lives, as she unconsciously remembers her life as a certain Bridey Murphy in Ireland 1798-1864 in great detail including her teacher, her father, her husband, her brother, local songs and dances of that time and finally even her death, how she died and what happened afterwards, going into the existence of afterlife in limbo and that drifting existence in a vacuum of nowhere - where she almost gets lost.
This increasingly hazardous experimentation ultimately risks getting out of hand, so that Ruth's mental health is put at risk, wherefore her husband steps down and will have no more of it.
However, the results already achieved, all documented on tape with witnesses, which sessions are truthfully revived on the screen, provide enough material for Morey Bernstein to write his book, which by no means is any proof of anything - who can even prove God's existence or anything metaphysical at all? - while it certainly is intriguing enough to raise discussions without end.
To this interesting intrigue comes the terrific acting by all persons involved, especially Louis Hayward and Teresa Wright as the hypnotist and his guinea pig, but all the others also are fully convincing - it's all perfectly organic, as Polanski would have put it. Thus it almost becomes like an documentary, and as such it is invaluable.
