Call the Midwife star Cliff Parisi revealed that he contracted hypothermia whilst filming series 13 of the BBC period drama.
While speaking at a press event, the actor, who plays Fred Buckle, told HELLO! and other journalists that it was "difficult to film" due to the chilly conditions whilst the cast were filming by the seaside in West Wittering back in September.
Although details of the episode have been kept under wraps, we do know that the Nonnatus House gang ventured out of Poplar for a "big day out".
"The wind was unbelievable. It was so cold," said Cliff. "I was wearing a shirt with a hanky on my head and I managed to keep it on my head for the whole time but I caught hypothermia in the end and they took me off set.
"I was hypothermic. It was cold," he added before confirming that he wasn't admitted to hospital for treatment but was taken off of the set to warm up with a foil blanket.
Cliff went on to say that his character was removed from the background of certain scenes as he was unable to film. "They just took me out of the background. We'd filmed all of the scenes that I was in, so they just took me out of the background of probably a couple of shots, that's all. It didn't really affect the schedule of shooting. To be honest, it was a laugh, it was just cold."
Annabelle Apsion, who plays Cliff's on-screen wife, Violet, added: "It was hysterical because the weather was fantastic just before we shot but while we were actually there, it could not have been worse."
The show's official Instagram account shared a photo from the set in West Wittering back in September.
Alongside a photo of Nurse Crane [Linda Bassett] and Miss Higgins [Georgie Glen] standing on the beach alongside an expectant mother, the caption read: "Last week our team took a special excursion away from the smoke-filled streets of the Sixties East End to film in the fresh coastal air of Sussex.
"The weather was....well, as you'd expect from England in September - sunny, rainy, stormy, bright, cold and warm all in one day!!!! But our intrepid crew made the best of it, and much fun was had by all!"
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Series 13 arrives on BBC One in the New Year. The upcoming episodes take place in 1969 and are set to cover "complex medical and personal situations on the midwifery and district nursing rounds".
The show will feature stories from within the Sylheti and Nigerian communities and from around the docks, tackling health issues such as Porphyria, Tetanus, Cerebral Palsy, Congenital Hip Dysplasia, and TB.
With more babies being born in hospital than ever before, "pressure on maternity beds remains extremely high across the country but Poplar is coping better than most due to the work of Nonnatus House and the popularity of home births under the auspices of the Sisters," the synopsis teases.