This is a devastating téléfilm adapted from the equally devastating novel of the same name by Charles-Ferdinand Ramuz, published in 1908 and also reviewed on this blog. It's a faithful adapatation, set in the Swiss mountains and depicting a very bleak environment of deep snow, marital infidelity, alcoholism, madness, murder and suicide.
The lead role of Jean-Luc is played by Maurice Garrel, the father of film director Philippe and grandfather of Louis. Jean-Luc makes his living felling trees and is married to Cristine (Frédérique Meininger), who loves Augustin (Philippe Mentha), but he left some time before and now she is married to Jean-Luc and has a baby by him. But then Augustin returns, Jean-Luc discovers that she's secretly seeing him, which she openlly admits with defiance, and so begins his rapid decline.
When their young child dies Jean-Luc refuses to believe it and continues to cradle the imaginary creature in his arms, drinks heavily and slides into psychosis. Cristine has a baby by Augustin, Jean-Luc locks both his wife and the child in a barn, sets fire to it and throws himself from a mountain.