California afternoon: six-year-old Lucy is critically injured in a hit-and-run. Good Samaritan Emma rushes her to the hospital but is blocked at every turn by her workplace rival Sarah, who is mid-tryst with her lover. Mistaking Lucy for Emma’s daughter, Sarah rams Emma’s car and intercepts the blood delivery out of spite, causing Lucy’s death. When dashcam footage surfaces, Sarah realises she has killed her own biological daughter. Her husband divorces her and exacts revenge; Sarah ends up insane in prison. Emma and Mike find healing through volunteering at the orphanage.