A woman who studies butterflies and moths tests the limits of her relationship with her lover.

My first stop at the London Film Festival. Coming hot off the heels off ecstatic buzz from a minority at the Toronto Film Festival, Peter Strickland's Berberian Sound Studio followup The Duke of Burgundy is a tantalising study of the power struggle between a sado-masochistic lesbian couple. The story focuses on their sexual role-play relationship, starting at an ambiguous point and continuing on until the cracks begin to show as inevitable diminishing returns develop.

While the first act sets the seed and plays it straightforwardly, the second act completely subverts everything we've seen in a fascinating way. While we at first believe their bond is more organic, it's revealed that a lot more is planned than we thought, and those boundaries continue to reveal themselves. While their sex lives are quite unique, or rather niche to a certain community, it's universally relatable to the demands, desires and generosity of the relationships in our own lives. What's most notable about the film is the two tones it switches between. Sometimes it can be ominous and deeply sensual while it explores the ritualistic but tender fetishism, conjuring a tense atmosphere quite like this year's Under The Skin or certain scenes of Mulholland Drive. This mostly derives from the mood setting music. But between those scenes it has an oddball sense of humour. It's a grounded and dry humour, one where we're laughing at them for their sexual quirks rather than with them.

The film even has a perfume credit at the beginning, winking at us, while the rest of the film takes itself dead seriously. It's a bizarre mix, but its consistency makes it the personality of the film even if it doesn't always blend well together. It can be quite funny when you get into it and most of that comes from the subtlety of the performances while the somber and erotic tone comes from Strickland's zealous stylisation. Unfortunately, Danish actress Sidse Babett Knudsen is unbearable in the first act. She's overly stilted and unnatural. However, as it's revealed that the quirks in her performance are deliberate, she begins to peel back the layers and sensitivity in her character and steals the show with just the acting in her eyes. Co-lead Chiara D'Anna gives ample support, being able to do a lot with very little, slyly showing her delicate and quietly sinister part of her character.

It's a cold film, one concerned with artificial superficialities rather than depth and emotion, best illustrated when Knudsen's character begins to wear loose fitted pyjamas rather than alluring clothing. As such, the story and characters are told entirely through their sex and foreplay rather than anything else. It often feels skin-deep. With its exclusively female cast almost in isolation, it's hard to ignore that the film and its sex scenes are seen through the male gaze of writer/director, rather than an authentic representation of what these relationships are most likely like. But even so, it is an interesting study of them with that in mind, moreso for their representation on film and the choices Strickland makes. Why is it when the rest of the film is so stern that when the characters express desires for a human toilet for their birthday that it's shown as funny? Why did Strickland choose to present it in this way and break the dreamy spell of the rest of the film? It appears to show a level of discomfort with his own characters and it thusly makes them difficult to embrace. It's best off when the film focuses on its amatory moments, even if they're ones of fantasy.

Fortunately, it's a very well produced film with rich production and lighting design that deftly combat the too-sharp-for-my-tastes contemporary cinematography. It's got quite a Gothic feel, one with period (the time and setting aren't clear, but it seems modern and English) and European sensibilities, especially with the score. The sound design is expectedly intricate and intimate, coming from this director of Berberian Sound Studio, at least. However, it's weak in the abstract moments. It never really justifies what moths have to do with the film, except being the profession of one of its leads and its namesake. It has attractive imagery no doubt, with a couple references to Stan Brahkage's experimental short Mothlight, but it's not very thematically inspiring. Although the film is often quite engaging and intriguing, its pacing and tunnel vision with the inherent repetition involved lead it to drag more than it should have and there were many times in its final twenty minutes when I thought it was going to end. It didn't really need to do much more.

With a more confident director The Duke of Burgundy could have been something more special, rather than being a Mulholland Drive lite in a few aspects. Although it can be graphic, it's relatively mild compared to what it could have been, not that it needed more than the suggestions it gives. Just could have been handled in a better way. It should have at least committed to either of its two dark and light tones. However, there's a lot to admire here, especially with the bold performances, and it does raise interesting ideas about the dynamics of control in relationships and sexual satisfactions. It'll still find its small patch of passionate fans, but it does as much progress for LGBT relationships in cinema as Blue Is The Warmest Colour, for better and worse."