Avenging Portia tells the story of two sisters. Sam leads a traditional life with her husband and young daughter, while Portia marries into the affluent Barrington family, renowned in the business world internationally. She soon finds herself the victim of abuse at the hands of her husband, Philip. Sam's concern for Portia's safety compels her to put her own safety in jeopardy. She puts together a plan in which to outwit Philip and gain her sister's freedom.