Although he is one of the founding fathers of modern documentary filmmaking, Frederick Wiseman’s ethos of discreet observation has meant that his work still remains relatively unknown. Never appearing in front of his camera, Wiseman’s 38th film, La danse, is a beautiful example of his signature “fly-on-the-wall” style, which allows his subject, the ballet corps of the Paris Opera, to speak for itself.

Set entirely within walls of the Palais Garnier, the 19th-century neo-Baroque opera house where the company rehearses and performs, Wiseman and his cinematographer, John Davey, track the development of seven ballets. Intimate long takes of the rehearsals detail contemporary choreographers Wayne McGregor and Angelin Preljocaj developing and refining movement phrases step by step. What a pleasure to be brought into the creative process as dancers go about their work unself-consciously. Slowly, we start to become familiar with certain faces and names, among them Mats, the stern sexagenarian choreographer, and Laetitia, one of the ‘étoiles’ of the corps.

As mesmerising as the dancing is, what goes on behind the scenes is also compelling. Wiseman turns his gaze on empty corridors, the cafeteria menu, sewing rooms, and the nightly clean of the 2,200-seat theatre. Gradually, another star emerges - Brigitte Lefèvre, the company's artistic director. Lefèvre comes across as a kind of maternal guru, reminding one new student and the watching audience that "to do is the most important."