Sophie is investigating the death of her sister, who disappeared while taking photos in the mountains accompanied by Bastien. Bastien is a rather taciturn mountain guide reputed to be a dangerous criminal.

The vilagers’ hotile attitude towards him is due to his staunch ecological view, which have, for several years, motivated him to wage war against real estate investors seeking to acquire building land. Certain villagers, consumed by their lust for wealth, decide to sell their land in spite of Bastien’s opposition. But the young guide is backed up by is uncle Gustave who also happens to be the district mayor. Things soon turn bitter…

Sophie enquête sur la mort de sa sœur disparue alors qu’elle prenait des photos en montagne en compagnie de Bastien, un guide plutôt taciturne accusé d’être un dangereux criminel. L’attitude hostile des villageois envers Bastien s’explique : c’est un farouche écologiste qui, depuis des années, lutte contre les promoteurs immobiliers cherchant à acquérir des terrains constructibles. Or, certains villageois, avides de bénéfices, décident de revendre leurs terres malgré son opposition. Le jeune guide est soutenu par Gustave, son oncle et Maire de la commune. Mais les choses s’enveniment rapidement…