Set against the backdrop of the Salinas Valley in California, the series retells the multigenerational saga of the Trask family, focusing heavily on the complex, destructive, and manipulative life of Cathy Ames (Florence Pugh). After marrying the idealist Adam Trask (Christopher Abbott), Cathy harbours hidden contempt for his romanticized vision of domestic life while engaging in a volatile physical connection with his brother, Charles (Mike Faist). Following the birth of their twin sons, Cal (Joseph Zada) and Aron (Joe Anders), Cathy shoots Adam and abandons her family to build an empire within the regional underworld, running a high-class brothel inherited from Faye (Martha Plimpton). As the twins grow into manhood unaware of their mother's true fate, Cal grapples with feelings of inherent dark impulses and intense sibling rivalry, echoing the Biblical narrative of Cain and Abel while navigating his family's legacy of betrayal and obsession.