Mathieu Grégoire is an esteemed author who lives in Spa with his wife and daughter and leads a carefully structured life. One day, while out in the desolate landscape of the High Fens he meets a mysterious woman whom he calls 'Belle'. An obsessive passion is kindled in Mathieu and in a short space of time he loses all control over his existence.

To attain knowledge, man and woman had to be willing to give up their innocence," says Boris Lehman. Life Lesson is a poetic and philosophic reflection on the theme of paradise lost. Some fifty persons illustrate the planet's convulsions and the world's vacillations. Trying to communicate, to commune with the invisible, they cry out, sing out, give out messages, each in their own way, in their own state of solitude. These are like multiple echoes that resemble waves in the water or stars in the sky. " Behind these images and sounds that have been stifled by today's society, Lehman hunts for noises, cries, songs, messages that go astray. He says that if we look at the invisible we may hear the words. He invites us to look beyond the appearances of social life and to vibrate in tune with life's polyphony that is all around us."