Miriam Margolyes joins Call the Midwife Christmas special as new episodes begin filming

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Mildred's arrival at Nonnatus House, with four Chinese orphans, is something of a surprise. The child refugees who accompany her had fled China and were found abandoned in Hong Kong. They are being adopted in the UK as part of the World Refugee Project.

These unexpected visitors bring both joy and chaos to Nonnatus House, what with Christmas preparations already underway and the midwives run off their feet caring for the expectant mothers of Poplar.

Also joining as new cast members are Harlots star Fenella Woolgar as Sister Hilda, The Last Kingdom’s Ella Bruccoleri as Sister Frances and Waterloo Road’s Georgie Glen as the surgery’s new receptionist, Miss Higgins.

Call the Midwife series eight rejoins the Sisters in spring time in 1964, with anticipation building for the birth of Prince Edward. Violet is holding a Teddy Bears’ Picnic and raising funds through a competition on whether the Queen will have a boy or a girl.

With the addition of the two new Sisters, Nonnatus House feels full once more. The midwives are introduced to their new midwifery bags, much to the distress of an already under the weather Sister Monica Joan who disturbingly absconds from Nonnatus House. Meanwhile, Nurse Crane is braced for a twin delivery but is confident the team can handle this smoothly.

Creator Heidi Thomas said: “It is an immense privilege to be starting work on series eight of Call The Midwife, and we can't wait to share the events of 1964 with our loyal and passionate audience.

“People often ask me how we can keep coming back year after year, but the answer is simple – we never run out of stories, and we never run out of love.”

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