Thanks to an unexpected surprise, the Christmas magic can find place in a grieving mother's home, while Nonnatus is rocked to the core when one of its own goes missing.
A new nurse called Barbara, who is anxious to prove herself gets off to a bad start. A family of neglected children is discovered and Trixie becomes determined to restore their health and bring happiness into their lives.
Barbara has to deal with her most challenging case yet after she helps a first-time mother as the birth does not to go according to plan. A new nurse shows up and soon makes an impression on Sister Evangelina.
After Poplar has a mysterious outbreak of dysentery, first-time mother Marie Amos's life ends up being turned upside down after her husband Tony is arrested for gross indecency with another man. Patsy attempts to help the young couple, as Tony faces a criminal hearing. Nurse Crane attempts to help a pregnant Irish woman with two young children are covered in flea bites and clearly malnourished.
Sister Winifred learns about Poplar's seedy underworld after she looks after Bridget Cole, an expectant prostitute. Shocked by the girl's lack of awareness, she has to use her past teaching experience and help from SGT Noakes in an effort to promote 'safe sex' to the local working girls. Barbara finds it hard to understand why expectant father, Frank Robbins, is so desperate to have a son.
A Christian Scientist couple refuse medicine for their newborn baby, leaving Sister Julienne questioning the nature of absolute faith. However, the case becomes more complicated when the parents are accused of harming their child. Barbara uses her initiative to communicate with a pregnant Sylheti woman who cannot speak English, although using the patient's young son to translate provides new problems. Sister Mary Cynthia returns to Nonnatus House and a woman catches handyman Fred's eye.
A diabetic teenager faces a tough time after falling pregnant, a situation complicated by her boyfriend's criminal past. Nurse Crane offers what support she can - but the girl's life is endangered when the young lovers go on the run. A case of petty theft brings a group of Irish travellers to the attention of the midwives, who end up treating a newborn infant and looking after an expectant mother, and it seems Fred's romance is on the up when he asks Violet to accompany him to a fundraising dance.
A water shortage means that the maternity home is busier than ever and two old schoolmates are reunited, but Marion shuns Shirley's attempts at renewing their friendship until they are brought together later in an unexpected way. Elsewhere, Barbara makes a revolutionary suggestion to help Sister Mary Cynthia treat the bedsores of her patient Tommy Mills, whose wife Gert may be more in need of care than he is. Fred thinks about taking the next step in his relationship with Violet.
Trixie and Sister Mary Cynthia team up to support a deaf mother-to-be, while another patient causes great concern when a case of morning sickness proves more serious than initially suspected. On the personal front, handyman Fred's daughter is less than delighted to hear about his forthcoming wedding. Will he be forced to choose between her and Violet?.