Having taken a young Chinese woman under her wing, teacher Emma Perotti finds herself on trial for the girl's murder.

Almost five years earlier, An-ling Huang walked into Emma's ESL classroom and into her family's life. Emma was drawn to the vulnerability she perceived in An-ling. An-ling, for her part, seemed to long for a surrogate mother and eagerly attached herself to Emma. Emma's husband, Tom, resented An-ling's intrusion and his wife's affection for her. Their son, Josh, developed his own relationship with her. Dredging up painful memories and buried grief, An-ling's presence threatened to tear the family apart.

Then An-ling is found dead, suffocated. As Emma's trial progresses, An-ling is revealed not to have been who she claimed, and we learn that the family members all have their own dark secrets.