The midwives welcome Sister Veronica, who's an instant hit with everyone – almost.
Lucille struggles with her mental and emotional health.
As Nancy harbors a secret of her own, Sister Veronica’s new case shocks Nonnatus house.
An emergency gastroenteritis outbreak is declared at the Nonnatus House.
Nancy oversees a child born out of wedlock, taking a very unexpected and shocking turn.
Sister Veronica spearheads an initiative to monitor the health of working children.
Preparations for the big wedding are underway; Nancy visits a homeless family.
The wedding day arrives, but a horrific car crash turns into a race against time.