April 1968. Racial tensions cast a shadow over Poplar, Nancy’s eyes are opened when she supports a dying woman, and Nonnatus House welcomes a new sister.

Sister Julienne helps care for a first-time mother who is going through a challenging diagnosis. Lucille struggles with her own health, and Poplar celebrates the Whitsun Maypole.

The death of a journalist at the center of a social media firestorm leads a veteran detective and her tech-savvy apprentice to a chilling discovery.