This is a stunning looking but eventually underwhelming film. Flawed but beautiful and probably best approached as an avant garde music video full of stunning images than for its narrative, what there is of it.
It is difficult to talk about this film without talking of the films it reminded me of. So to get a feel for it, imagine a hybrid of Daft Punk's Electroma (the robot guardian, the melting faces and the general feature length music video vibe), Tetsuo II (the siblings experimented on by their father in flashback playing out their final conflict in the present; also the way that during the experimentation the characters duck under the surface of reality - although rather than doing so to merge with metal as in the Tsukamoto, here their faces and bodies melt and distort under the pressure from the drugs), the 70s avant-garde shorts by Clive Barker (the flashback scene has lots of images almost in negative or highlighting certain aspects of the characters bodies in black against a blinding white background), The Man Who Fell To Earth (Barry removing his 'appliances' and the melting hallucination scene), Equilibrium (the use of drugs to alter or suppress moods), 1984 (Elena's hidden diary and photograph), Argento (the characters crawling along corridors that are enormous blocks of primary colours and Elena communing with nature), Scanners (the telepathic powers of Elena), the 1970s 'escaping from society' sci-fi films such as Logan's Run and THX-1138 (the shots of Barry driving his sports car in this film are almost direct references to the framing of Duvall inside his car in the chase sequence of THX) and especially 2001: A Space Odyssey (the distorted landscape shots and 'drug trippy' scenes being the gateway to apparent godhood, or at least delusions of grandeur!)
I particularly liked the way that many of the scenes are filmed almost as if the camera is short sighted, which pays off in Barry's reveal of what the experiments have done to him. I really like films where you have a 'successful' experiment having a confrontation with a 'failed' one, with them swapping roles at the mid-point with the flashback realisation, and how that realisation affects the usual self-assured characters.
Beyond The Black Rainbow does have two flaws however. The first is that it is extremely drawn out for what plot it does have. It falls into the trap of portentous oblique dialogue delivered in slow passages which do not really explain anything. Elena's drugged out escape from the facility also has to be in the running for slowest escape scene in history! I really liked these aspects however, especially when I got into the hypnotic mood of the scenes, but I could also see them driving other people crazy!
The second flaw is the really major one:
in which just before the final confrontation Barry gorily butchers a couple of stereotypical drugged out young campers blasting death metal at full volume in the woods. I guess there is the slight idea there of the psychopathic results of medical experimentation into drugs confronting your casual stoned-out users but that generic slasher scene appears completely out of nowhere, with the campers being people we had never met before and there being no wider implications springing from the inclusion of the scene except to show some gore. That scene sadly almost totally ruins the pseudo-intellectual, ambiguous tone that the film has been building for the previous 90 minutes, whereas while the film might be narratively flawed before that it is at least tonally all of a piece. It is as if Bela Tarr included a scene from Transformers five minutes from the end of The Turin Horse!
Apart from that rather misjudged scene near the end I liked the film very much. It may eventually be less than the sum of its parts without much going on narratively but it is worth a look for the gorgeous visuals and the 1980s setting augmented by the fantastic electronic soundtrack.