A jaded director, an aspiring actress, a tricky shoot, a producer who's not amused: Corneliu Porumboiu is not treading new ground in his third long feature; there are so many films on the topic of filmmaking, from the worst (Interior.Leather.Bar) to the best (Day for Night, The Player, The Rest Is Silence).

But what he manages to achieve with the most polished of formal means and a razor-sharp script is a little miracle. HBO screens the pic starting with this Thursday, March 7, at 8pm, so save the dates.

For those who love his previous films, your truly included, watching Când se lasă seara peste București sau metabolism/When Evening Falls on Bucharest or Metabolism might be a mind-scratching, highly cerebral experience. It certainly took me a second viewing and lot of thinking to appreciate the film for its intelligence, brilliant connection between form and content, and its great sense of irony and sly humor.

The plot doesn't consist of much more than the elements above: a (still) young director fakes an ulcer to skip the shoot for the day and spend time with his lover, a promising young actress. They have sex, go out for lunch, meet another filmmaker, rehearse a scene until it become almost ridiculous, and discuss food, cultural differences, and whether means define content.

Meanwhile, his no-nonsense producer smells foul play and asks him to provide proof for his health crisis. And to add more trouble, his main actor has just trashed a hotel room.

The unhurried, matter-of-fact style of the dialogue and episodes extends to the film's form as well: the staging is minimalist, the camera is static and never zooms to a close-up of the actors, the cuts are rare, the acting is unemotional.

But there is excitement and humor to be found in the ingenious variations, the dry, ironic wit of the dialogue, and the break between what the characters say and do and what Porumboiu shows. While the director talks about how difficult it is to shoot on film, with its restrictions such as the maximum length of eleven minutes, Porumboiu shoots his film on 35mm and lets each scene run in real time up to eleven minutes.

When the actress and the director discuss whether it's gratuitous to shoot a nude scene and rehearse that said scene clothed and until they are completely frustrated, shrewd Porumboiu shows some naked skin. Does form influence content, or is it the other way around? It has certainly always been important in his films and in this one it can (finally) play the main part.

Metabolism is certainly no film for the impatient or those unwilling to work their way through it: it's slow, hermetic, and constantly challenging but for anyone interested in art, its physicality and effect, and general human interaction, this is pure gold. Not to mention it's also a fun take on a love story, or, to be more precise, a non-love-story.

Metabolism is neither as laugh-out-loud funny as Porumboiu's debut 12:08 East of Bucharest or tense like the subsequent Police, Adjective but it's nevertheless a though-provoking work from a director who reinvents himself with every new film. And one really has to give it to Porumboiu: he has never written an end scene which was less than perfect.

PS: The ending also offers the perfect solving of the puzzling: for the first part you'd have to wait for the end credits while the second part relates most directly to the hero's inner organs, as shown in the hilarious penultimate sequence.

By Ioana Moldovan, columnist, ioana.moldovan@romania-insider.com