Nurse Jenny Lee arrives at Nonnatus House in London's East End to begin her work as a midwife. Naive and unused to the harsh conditions of the borough, she must rise above her misgivings if she is to succeed in her new role.

A new midwife, Chummy Browne, arrives at Nonnatus House, and finds it difficult to prove herself. Meanwhile, Jenny befriends a young Irish prostitute who is expecting a baby, and is shocked by the Church's treatment of the girl.

Jenny befriends an old soldier named Joe, and is disturbed by his living conditions. She is also visited by a man from her past, while Trixie and Cynthia have a sensitive case to deal with, and Chummy is asked on a date.

A new baby is snatched from her pram, sparking an area wide search. Jenny is more familiar with the kidnapper than she realizes, Cynthia blames herself when a patient becomes gravely ill, and Chummy's romance continues.

A figure from Jenny's past makes contact, while Jimmy continues to pursue her. Chummy prepares for an important meeting, and everyone at Nonnatus House rallies round the building's cleaner, Peggy, whose brother is very ill.

Jenny speaks to her ex-lover again, while Sister Monica Joan lands herself in trouble with the police. Chummy receives a visit from her snobbish, imperious mother which forces her to reconsider her relationship with Peter.

Nonnatus House is alive with preparations for Christmas. Chummy is arranging a nativity play with the Cub Scouts, Jenny is faced with a difficult case, and a young girl's predicament leads to a big decision.

Jenny tries to help a battered wife, Doctor Turner finds himself overcome with requests for nitrous oxide from pregnant women throughout Poplar, while Trixie and Sister Evangelia help deliver a baby in very unsavory circumstances.

Chummy makes an important decision, Jenny reconnects with Jimmy, and Cynthia's conduct is called into question after the death of a baby she delivered.

Jenny encounters racism firsthand when assigned a Jamaican patient, while Cynthia has to deal with a cantankerous man suffering from diabetes. Sister Bernadette avoids Doctor Turner, and a familiar face returns to Nonnatus House.

Sister Bernadette is discharged from hospital, while a heavily pregnant Chummy resumes her midwifery duties. Jenny meets a new love interest, Fred's pregnant daughter pays him a visit, and Nonnatus House itself is under threat.

Nonnatus House and the surrounding area is evacuated when an unexploded bomb is found nearby. Meanwhile, Shelagh has doubts about her wedding to Patrick, and Jenny and Trixie help a man who is suffering from shell shock.

Now dating surveyor Alec, Jenny joins the other midwives in their superior new base, along with latest recruit, Sister Winifred. Jenny is concerned for Merle and Billy, a young couple whose infant boys are permanently ill, causing them to doubt their parenting skills, whilst added is stress provided by the fact that Billy's brother died as a toddler. Surprisingly, Sister Monica Joan accidentally provides Dr. Turner with the solution to the children's complaints, thus saving them. Chummy, meanwhile, drums up support for the newly opened, but under-used ante-natal clinic, taking advantage of a royal visit to put it in the spotlight. The day is a success, and to add to it, Chummy helps an older woman with a difficult birth, resulting in Sister Julienne asking her to return to work.

Jenny is promoted to Acting Sister at the clinic, much to the chagrin of the more experienced Trixie. Meanwhile, Cynthia is taken in by the theories of a visiting doctor, and a troubled, desperate woman seeks help.

Sister Julienne and Trixie attend to the female inmates at Holloway Prison, where they meet a troubled young woman. Meanwhile, Jenny deals with a vain patient, Shelagh receives horrendous news, and the girls celebrate Chummy's birthday.

Sister Winifred treats a young Jewish woman whose mother is plagued by remembrances of the Holocaust. Meanwhile, Shelagh tries to find a new way to channel her energy, and Alec suffers a terrible accident.

As Jenny takes compassionate leave after Alec's death and Sister Julienne collapses with exhaustion Shelagh returns to help out and efficient nurse Patsy Mount arrives. They start to plan for a party to mark the jubilee of Sister Evangelina taking holy orders but are interrupted by irate Mrs Harper, whose daughter Sally, a young woman with Downs Syndrome, is pregnant. The father, cerebral palsy sufferer Jacob, lives in the same residential home and they declare that they are in love and aim to marry but the baby is stillborn and Jacob is sent to another home. News of Evangelina's celebration attracts her brother Vincent, now an alcoholic tramp, and she steals food for him and sees him admitted to hospital, but her party goes ahead - despite her protests - and the community shows their appreciation of her work over the years.

Patsy's brusque manner sees her taken off midwifery duties and reassigned to district nursing, where a patient reminds her of her past. Meanwhile, Trixie deals with a couple whose relationship has separated them from their families.

Jenny returns and is seconded to the London Hospital, where she meets a fretting mother-to-be. Meanwhile, Chummy's mother visits, a patient of Cynthia's becomes mentally ill, and Tom's nervousness leads to trouble with Trixie.

Chummy struggles to cope with her mother's terminal illness, with her experience affecting Sister Monica Joan greatly. Meanwhile, Shelagh and Patrick receive encouraging news, and Jenny makes an important decision.

As Christmas approaches, Chummy and Trixie are organizing a concert. Meanwhile, Patsy takes a pair of pregnant girls to a mother-and-baby home which proves to be ill run, and Cynthia is conflicted about her future.

A new midwife arrives at Nonnatus House, and finds it hard to fit into her new role. Meanwhile, Chummy moves into the mother-and-baby home, Trixie helps a young boy in terrible need, and Sister Evangelina is in denial about her illness.

As dysentery sweeps through the area Trixie takes on her first official duty since her engagement to vicar Tom by organizing the Rose of Poplar contest whilst Phyllis is concerned for sickly Dolores McEvoy, who is living in a filthy hostel apart from her husband but is too ashamed to give the address. When Phyllis locates the hostel she also finds the source of the dysentery. Meanwhile young father-to-be Tony Amos is the victim of police entrapment when he goes cruising in a men's toilet. Dr Turner speaks up for him when he is taken to court but, although prison is avoided, bigoted attitudes make life difficult for him and his wife and the nurses' opinions are divided.

Sister Winifred meets a young prostitute and begins a campaign to improve the lives of women like her, Trixie reconsiders her engagement when Tom is offered a post in Newcastle, and Sister Monica Joan is unexpectedly called into action.

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.

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.

As Christmas approaches, an outbreak of measles hits Poplar. Meanwhile, Tom receives an intriguing offer from the BBC, a face from Patsy's past returns, and Sister Monica Joan goes missing.

One of Patsy's patients is diagnosed with typhoid, which reignites painful memories, Sister Winifred is deeply affected by the case of an unwed mother-to-be and Tom asks Barbara out to dinner.

A series of attacks on young women in Poplar has a direct impact on the residents of Nonnatus House, Trixie is suspicious about a patient whose pregnancy has not been reported, while Patrick and Shelagh take a trip.

Patrick is horrified to learn that a medication prescribed to expectant mothers may be the cause of the recent birth defects in Poplar, while the Nonnatus House residents and the community at large are devastated when tragedy strikes.

The Nonnatus House staff face great change, Phyllis and Barbara help a battered wife, while Sister Mary Cynthia becomes increasingly fragile.

The effects of thalidomide continue to take their toll on a former patient, leaving Patrick guilt-ridden, while a shocking incident leaves Phyllis consumed with guilt of her own.

A figure from Jenny's past makes contact, while Jimmy continues to pursue her. Chummy prepares for an important meeting, and everyone at Nonnatus House rallies round the building's cleaner, Peggy, whose brother is very ill.

Jenny speaks to her ex-lover again, while Sister Monica Joan lands herself in trouble with the police. Chummy receives a visit from her snobbish, imperious mother which forces her to reconsider her relationship with Peter.

Jenny tries to help a battered wife, Doctor Turner finds himself overcome with requests for nitrous oxide from pregnant women throughout Poplar, while Trixie and Sister Evangelia help deliver a baby in very unsavory circumstances.

As Christmas approaches, Chummy and Trixie are organizing a concert. Meanwhile, Patsy takes a pair of pregnant girls to a mother-and-baby home which proves to be ill run, and Cynthia is conflicted about her future.