Oh, those incorrigible romantic poets. They were forever sleeping with their sisters, falling drunkenly out of windows and dying violently in Greece. Cool your brow. Justin Hausner's very austere follow-up to the already quite austere Lourdes – one of the most underappreciated films of the last decade – takes a less-heated Prussian perspective on the movement. Christian Friedel offers us a humourless version of the still-fashionable writer Heinrich von Kleist. Hausner's script is concerned with the notorious nature of his death: the poet and novelist is believed to have entered into a suicide pact with a terminally ill female acquaintance.

That's certainly a big enough story for a feature film. But the focus is so contained that Amour Fou feels a little like an overextended short film.

The delicate, internalised Birte Schnoeink plays Henriette, loyal wife to a caring, if desperately dull husband who has something to do with money and government. In these circumstances, the arrival of a romantic writer would, usually, bring a whirlwind of temptation, but Heinrich seems, if anything, even less energised than Henriette’s sober partner. Initially, she refuses his tempting offer to die together violently. Then her circumstances change.

The plot barely reaches a crawl. But Hausner's formal rigour is undeniably hypnotic. Despite the hugeness of the decisions being made, there is barely a voice raised or a tear shed throughout the film's duration. Amour Fou could hardly seem more like an exercise if it were enacted with hand puppets. That is its strength. That is its weakness.