A chance encounter with an impoverished child forces Trixie to see an unfamiliar darker side of life. As Nonnatus House welcomes a new resident, Nurse Barbara Gilbert, Tom Hereward has a surprise romantic gesture in store for Trixie.

Barbara faces her most challenging case to date when she treats first-time mother Abigail Bissette and the birth does not go according to plan. As Sister Julienne struggles with the increasing financial pressure on Nonnatus House, a mystery benefactor comes to the rescue. Elsewhere Sister Evangelina is unimpressed by newly arrived nurse Phyllis Crane.

The Nonnatus team rallies to support first-time parents Marie and Tony Amos when Tony is arrested for gross indecency with another male. Elsewhere, as Poplar is gripped by an outbreak of dysentery, Trixie undertakes her first official church duty since her engagement to Tom.

The midwives face one of their busiest nights to date, whilst Sister Winifred concentrates her efforts on the prostitutes of Poplar. Elsewhere, cracks start to appear in Trixie and Tom Hereward's relationship.

Sister Julienne's faith is challenged when a mother refuses medicine for her newborn baby. Dr Turner's involvement in the case forces him to face his own demons. Meanwhile, Barbara must work out a way to communicate with a pregnant Sylheti woman.

Phyllis deals with a diabetic teenager who has fallen pregnant, Sister Mary Cynthia comes into contact with a group of Irish Travellers, and Patsy organizes a square dance to raise money for the Cubs' trip to Norfolk.

A pair of school friends are unexpectedly reunited in the delivery room, and a mix up results in complications for both. Meanwhile, Barbara helps a couple in need of assistance, and Patsy's secret relationship with Delia pains them both.

Trixie and Sister Mary Cynthia help a deaf-and-dumb woman, and Barbara has a baffling case. Meanwhile, Fred's daughter arrives from Birmingham and interferes with his and Violet's engagement, and Delia has a proposal for Patsy.

Festive cheer is in plentiful supply as Poplar readies itself for Christmas. An unexpected surprise for a grieving mother helps bring the Christmas magic home, while Nonnatus is rocked to the core when one of its own goes missing.

When a baby is born with severe deformities of the kind later identified as caused by the drug thalidomide, the midwives find it difficult to handle the situation, and the baby's father rejects her completely, to his wife's dismay. Trixie's new sideline as a keep fit instructor brings her into conflict with Sister Julienne, and she also becomes suspicious of the relationship between Barbara and Tom. Rather than return to Wales as her mother wishes, Delia moves into Nonnatus House.

Barbara treats a pregnant woman whose dockworker husband is struggling to support her as opportunities for work dry up. She is forced into a difficult decision that leaves Barbara facing the biggest test of her career. Nurse Crane meets a kindred spirit when she learns to speak Spanish, and Sister Evangelina helps a woman with breastfeeding, leading to unforeseen consequences.

A outbreak of typhoid erupts, and suspicion over who the carrier could be threatens to break apart a closely knit family. Sister Winfred faces a personal dilemma when a local teacher is revealed to be pregnant by a married man. When the woman takes matters into her own hands, Sister Winifred is forced to consider the role her own prejudices may have played. Meanwhile, Barbara inadvertently agrees to go to dinner with Tom, but is wracked with worry about how Trixie will react.

Sister Julienne is seconded to a maternity ward, and is impressed by how modern technology is being used to help the mothers - but is left with a moral dilemma after assisting on a traumatic birth. A young man from Poplar is delighted to be accepted into university, but his mother is less than happy. His dreams are jeopardised when his girlfriend gets pregnant, a development that puts pressure on the whole family.

Turner and Shelagh are at the forefront of the advances in medical technology, and begin a campaign to ensure better respiratory health for their patients. However, Timothy fears their own lifestyle is not good for them and tries to encourage his parents to give up smoking. Violet injures her back and is forced to leave the shop in Fred's hands, a decision that strengthens their relationship but which proves to have other, unforeseen consequences. A new mother's past comes to light, with devastating repercussions for her family. Nurse Crane draws on her own experiences to help her.

Poplar is rocked by a series of violent attacks on women, and a prostitute is too ashamed to report what she knows - but her actions lead to a dangerous man roaming the streets, with devastating consequences for the residents of Nonnatus House. A mother tries to keep her daughter's pregnancy a secret to avoid gossip, putting her life in danger. The Turners go on a long overdue holiday, but the weather ruins their plans.

The introduction of the contraceptive pill is welcomed by Dr Turner, but some of his colleagues are less keen on the idea. Patsy tries to help a bargee who wants to give birth among her own community rather than in a maternity ward. Nurse Crane deals with an emergency during a storm, and a familiar face returns to Nonnatus House - but has been changed by her time away.

Dr Turner is horrified to realise he may be partly to blame as the cause of the recent rise in birth deformities comes to light, and tries to prevent further cases. Sister Evangelina returns to work, but has clearly been affected badly by her stroke, and her health continues to deteriorate. A pregnant bride goes into labour during her wedding reception, while her mother is forced to come to terms with her grandchild being conceived out of wedlock.

The nuns are trying to help a tiny struggling mission hospital on the Eastern Cape. But can they save the hospital from closing down – and perform a Christmas miracle a long way from home?

The team reunite but all is not well when a change of management shakes up Nonnatus House.

An explosion at the docks brings heartache to the people of Poplar, whilst Sister Ursula continues to ruffle feathers with her unpopular decisions.

The winds of change are blowing through Poplar, as a new government paper calls for the eradication of small hospitals in favour of large general hospitals. Dr Turner and Shelagh are informed that an inspection of the maternity home will decide its fate.

An expectant mother with financial struggles enters into a painful arrangement with her cousin. As Tom provides pastoral care, he reveals why this case touched him more than most.

Nonnatus House welcomes a new recruit, Nurse Valerie Dyer. A vulnerable young man captures Fred and Violet's hearts, whilst the whereabouts of Sister Mary Cynthia is a concern.

Valerie Dyer cares for a pregnant Somali woman and is shocked by aspects of this unfamiliar culture. The nuns and midwives try to provide the best care for Sister Mary Cynthia.

Dr Turner helps the Mullucks cope with the stresses of caring for a disabled child as the terrible legacy of thalidomide becomes apparent and Nurse Crane faces an unexpected crisis.

An unexpected turn of events leads to a wedding being hastily arranged. Shelagh finally goes into labour. The arrival of the pill leads to unforeseen consequences.