This seems like an odd movie. There were a lot of movies about mental illness in the 70's like "Sybill" and "I Never Promised You a Rose Garden", but the topic didn't exactly seem ripe with erotic potential. But this movie isn't really the porn industry trying to do a cheap, exploitative porn knock-off of a mainstream movie so much as it is the porn industry trying to CROSS OVER into the mainstream by making a sex-filled but SERIOUS movie with some amount of genuine production values (i.e. something besides sex). It isn't entirely successful, of course, but it is interesting.
The top-billed star in this is Harry Reems from the notorious "Deep Throat". He is again playing a doctor, but a serious one this time (sans the stupid German accent). Reems was not a great actor, but he was an actor, not just a giant walking erection like most subsequent male porn stars. The real star here though is the never-to-be-heard-from-again Shawn Harris who plays "Susan". She gives a genuinely good performance (even by non-porno standards) as a girl who seems to suffer from both catatonic schizophrenia and multiple personality disorder as the result of past abuse. Most of the movie is flashbacks of this abuse or romantic fantasies involving her handsome new doctor. Harris is genuinely believable and disturbing in the vulnerable "Susan" role and she essentially plays a second role as "Susan's" tough alternate personality "Sandra". And she is also genuinely pretty, not just sexy like most porn starlets. I didn't see the uncut XXX version, so I don't know if she actually did hardcore, but regardless as an actress she is much closer to Meryl Streep than to Jenna Jameson. She was also involved in the music, which is definitely 70's-style sappy, but also strangely haunting.
Jennifer Jordan, who plays Reems long-suffering wife, is also quite attractive if much more of a traditional female porn star. Fans of straight sex movies will not be totally dissatisfied with this. Personally, I don't think it's a problem that this is only currently available in the "soft" version--hardcore sex would definitely NOT improve this anymore than showing the characters sitting on the toilet taking a crap would. If you do want to see a hardcore version of something like this though, check out "Defiance of Good". On the other hand, if you want to see an even more bizarre, surrealistic (if not as well-made) film in this vein, check out "Synthia, the Devil Doll."