The Girlfriend is a psychological thriller miniseries (six episodes) based on Michelle Frances’s novel.  It stars Robin Wright as Laura Sanderson, Olivia Cooke as Cherry Laine, and Laurie Davidson as Daniel Sanderson.  The story focuses on the complex and volatile relationship between a mother, her son, and the son’s new girlfriend.

Daniel, a medical student, brings Cherry Laine into his family’s orbit. Laura, his mother, who has always had a close — perhaps overly close — relationship with Daniel, is struck with suspicion from the beginning.  Cherry is charismatic, witty, working in real estate, and seems to navigate the upper‑class environment of Daniel’s family quite well; but Laura thinks Cherry may have hidden motives.  The tension builds from contrasting points of view: we see events both from Laura’s perspective and Cherry’s, which makes it unclear what is real, what is manipulation, and who is more at fault.

As Cherry becomes more serious with Daniel, the friction with Laura escalates. Laura digs into Cherry’s background, trying to find evidence that supports her fears. Along the way, Cherry seems to respond in ways that could be defensive, or could imply duplicity. For instance, Laura uncovers a video, inconsistencies in Cherry’s stories, and perceives Cherry sabotaging or manipulating situations. Cherry in turn accuses Laura of being controlling and unable to let Daniel have independence.

In the final episodes, the stakes become dangerously high. After Laura lies to Cherry that Daniel is dead (in order to drive a wedge between Cherry and Daniel), Cherry retaliates in various ways, including causing trouble for Laura professionally, manipulating events to make Laura look bad, and even physically confronting her.  The confrontation culminates in a violent fight between Laura and Cherry near a swimming pool. Daniel, drugged by Laura, intervenes, leading to tragedy. Laura dies as a result of the struggle.

After a time‑jump, Daniel and Cherry are together, married, expecting a child, and living in what seems to be a restored peace. But the ending is ambiguous: Daniel discovers a recording made by Cherry’s mother warning about Cherry’s manipulative nature. This raises the question whether Cherry really was as benign as she seemed, or whether Laura’s suspicions had merit after all.  The series ends on this note of uncertainty, leaving unresolved the moral balance between Laura and Cherry and whether the audience should trust one or the other.