If you are interested in seeing horror films that take a particular aspect of child-rearing, one that is fear-inducing for any parent or to anyone who has any experience in raising children, you may well enjoy this underplayed film. While watching it I became quickly convinced that it was a partner film to 'Grace' (2009). Although very contrasting aspects of child-rearing are turned inside-out as permitted within the possibilities offered by the horror genre, both are relatively underplayed and with small casts; the photography is subtle and although there are sudden jolts designed to shock, they really do resemble those moments when you're so tired you literally fall asleep while you're on your feet. Or at least that is what the victimised parents keep trying to convince themselves as they become more unhinged as every hour passes without rest. Grace, in its ambiguity and horrific content, is certainly a more interesting horror film. But the actresses who play the mothers in both films resemble one another not only in looks but in their obsession with taking care of their child. After checking the background info of both films, I was initially convinced they had the same director; but on closer observation I discovered that the names differ by one letter! Paul Soter directed Grace, whereas this film was directed by Paul Soler. Watching both parents gradually descend into madness as they become deprived of sleep is done hauntingly; you quickly realise where the title comes from; not crop circles or dark spirits but the lines that form under your eyes thanks to long-term weariness. The film makes use of three sets of possibilities, and thankfully doesn't reveal too quickly which one of them is true: are they hallucinating the spectre who seems to be appearing in their house, on cameras and in reflections, is their house haunted or is there a real person threatening them? Although I haven't raised a child or been kept awake by one, I certainly know how scary it can be when you lose track of time through lack of sleep and you're no longer sure which day it is, and this film milks that given for everything it's worth. It turns out that the director of Grace and Dark Circles are entirely unrelated, just as the tidy resolution presented in this film contrasts to the horrific and unexplained horrors of Grace. Still, this film was haunting, original, well-acted and is sufficiently under-played to be worthy of more than a single glance. It doesn't have a great deal to offer, but what it does present it presents in a sufficiently haunting package to give you food for thought, which as far as I'm concerned is the primary function of any truly good horror film.