The brutish John Gourlay is a merchant in the village of Barbie, envied and resented by the villagers because of his success, which is symbolised in his prestigious house with green shutters. He dominates and bullies his family, in particular his gifted, sensitive but weak son. 

Ultimately, his refusal to acknowledge the arrival of the railway and to adapt to the increasing industrialisation of Ayrshire precipitates murder, suicide and his family's tragic downfall.