It's October 1967, which brings new beginnings with Nurse Crane away on an exciting adventure of a lifetime and Trixie taking care of her godmother in Portofino. Sister Hilda runs a tight ship, and Shelagh has joined the team to ease their busy workload. Lucille prepares for her first day back at work but is clearly not coping well, despite the support of the team.

Sister Monica Joan is spooked to find a black raven in the parlour, believing its presence to be an omen. Seeking interpretation of the raven's meaning, Sister Monica Joan connects with Dulcie Greenhlagh, an eccentric East End clairvoyant, but soon realises there is another reason they were destined to meet.

Matthew discovers one of his warehouses is being used by squatters, including a heavily pregnant woman. Shelagh faces the most challenging delivery of her career. Dr Turner attends a district health committee meeting on measles vaccination. He hopes to increase uptake by running a pilot scheme in Poplar.

Nonnatus House faces its darkest day after a tragic incident in the heart of Poplar. As the community rallies together, the team must overcome personal anguish to help the injured.