La bête humaine

Jacques Lantier is a locomotive engineer who works the Paris-Le Havre route. His colleague Pecqueux, who admits he has a wandering eye despite being happily married, laments Lantier's loner status, Lantier in return saying he married to his locomotive, which he's named Lison. This loner status is only a front, his so-called marriage to Lison largely meant as a distraction to keep his mind away from human romantic love which he believes cannot be part of his life. While Lantier is on a personal train trip in an extended layover in Le Havre, the murder of an elderly man named Grandmorin is committed aboard the sparsely occupied train. In not mentioning what he saw to the authorities, Lantier covers for who he believes committed the murder, namely Roubaud, the La Havre stationmaster, and his innocent looking wife, Severine. They did indeed commit the murder, it orchestrated by Roubaud in having discovered Severine's affair with Grandmorin, her godfather, the murder committed by both meant to tie them together emotionally in keeping this secret. Conversely, Lantier didn't divulge to the authorities what he saw in his feelings of love for Severine from afar. While Lantier protecting the Rombauds was not meant to lead to anything, it does lead to an emotional bond between himself and Severine, the two who embark on an affair of their own in Severine knowing that the murder has only further torn her marriage apart. Fearing for her life at the hands of her husband who has become more and more despondent, Severine tries to convince Lantier to kill Rombaud before he kills her. What happens is affected by Lantier's secret about himself and why he didn't see love in his life.