Ahead of the Call the Midwife Christmas special, Sister Julienne star Jenny Agutter warned that the two-parter – set in Poplar and Hong Kong – contained some “very disturbing” moments.

But that won’t have come as a surprise to longtime fans.

Heidi Thomas’s BBC drama, following the midwives and nuns of Nonnatus House in London’s East End from the late 1950s to the 1970s, is often described as a warm hug, but it doesn’t shy away from the hardships and horrors some face.

And that was especially evident when it came to May Turner’s biological mother, Esther, and her young son, Christopher.

When Shelagh first learned that Violet would be travelling to Hong Kong to visit one of her sons, she asked the mayor to deliver a letter and photographs of May to Esther, from whom they hadn’t heard anything in more than a year. The sisters at the Branch House there, which collapsed in the special after the ground beneath it gave way, had spotted her occasionally, but the prolonged silence was deeply unsettling.

However, Shelagh decided to join the Nonnatus House party in Hong Kong and took it upon herself to find Esther – only to discover she had disappeared.

It later transpired she had lost her job as a nanny for a British service family, and no one seemed to know where she had gone.

The Turners, determined not to “abandon” her, persisted in their search, even after being warned off by one of Esther’s terrified friends. Her fear – and the presence of her gangster husband – hinted at something far more serious.

Still undeterred, the couple continued, at one point fearing that Esther and Christopher had become separated, prompting Shelagh to seek out Sister Edith for more information. Thankfully, the nun was able to direct her to Esther’s new whereabouts – living in shocking slum conditions – as well as revealing the alarming reason for her disappearing act.

Esther had gone into hiding because Christopher’s father is The Cormorant, a gangster of the “worst kind” who has fathered many children with many women. But Christopher is his only son – and he intends to take him.

“You have not seen a man like this,” warned Sister Edith. “He has ordered her and her child to be hunted down like dogs.”

Fearing her child would follow in his father’s criminal footsteps, Esther fled – a decision made all the more agonising because she knew she wouldn’t be able to take her baby daughter with her, instead leaving her in a cardboard box outside Hibiscus House, trusting the sisters to care for her.

But the situation has since become even more desperate…

On examining Christopher, Dr Turner immediately knew all was not well. And after finally persuading Esther to leave their squalor, he took the boy for an X-ray, which confirmed he has Wilms tumour (nephroblastoma) – a type of kidney cancer that predominantly affects young children.

Two men stand in a small, sunlit medical office, facing each other on either side of an illuminated X-ray. The man on the left, dressed in a beige waistcoat and rolled-up shirt sleeves, looks concerned as he studies the image. The man on the right, wearing a green military uniform, listens intently with his hands clasped in front of him. Behind them, anatomical drawings hang on the wall above the X-ray viewer, while medical trays, books, and equipment sit on nearby shelves and desks.

Stephen McGann. BBC/Neal Street Productions/Charmaine Man

With Esther’s permission, Dr Turner planned to take Christopher to London, where a new form of chemotherapy was being trialled – described as “brutal but spectacular”, and the only cure for this illness.

“We may not have years or months if we don’t act fast,” Turner stressed, desperate to get Christopher out of Hong Kong.

But that plan appeared to fall apart when The Cormorant learned that his son was about to be taken overseas, sending one of his men to seize Dr Turner, who was ambushed while collecting medical supplies with Fred.

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The gangster – who previously lived in Liverpool before being deported during the war – refused to let his son leave, before insisting he would only agree if Dr Turner beat him at gambling, which he knew would never happen.

But Turner refused to play, instead appealing to his ego.

“If Christopher’s life is lost, who will pray for you? Who will carry on your family line?”

When The Cormorant insisted he could find a Chinese doctor to save his boy, Turner responded calmly: “It doesn’t matter who saves his life, as long as it’s saved. And if it is saved, I guarantee I will send him back to you.”

And that seemed to do the trick.

As armed police raided the premises, The Cormorant relented, instructing Turner to take his son to England, where he will stay with the Turners while undergoing treatment – not permanently, however, with the doctor telling Fred that they have no plans to adopt him.

But what is his survival chances?

According to The Instituue of Cancer Research, five-year rates were 59 per cent in the early 70s, rising to over 90% today. But survival is significantly lower if the disease is to return.

So, the road ahead for Christopher is undoubtedly long. But now that he’s guaranteed to receive the very best medical treatment, not to mention first-rate care from the Turners, heres’s hoping season 15 will have a happy ending.

Call the Midwife season 15 arrives on BBC One and BBC iPlayer in early 2026.

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