Laura appears to be the perfect mum, wife and lawyer, but she harbours a dark secret; when she meets a kind stranger named Emily, she begins to realise there's more to her new friend than she lets on.

Laura blacks out following a wild night on the town with Emily, putting her marriage at risk; as Laura tries to piece together what happened, Emily embeds herself deeper into her life.

After discovering that Emily isn't who she claims to be, Laura sets out to find answers; with her husband leaving for the U.S. and a journalist poking into her past, Laura nears her breaking point.

When Laura confesses her secret, Emily forces her to face her past while also plotting to expose her to the journalist; as Emily works to tear Laura's family apart, the tragic connection between the women is revealed.