Call the Midwife casts star of The Traitors in Christmas special

Maddy was a faithful in the series with correct suspicions about traitor Wilf (as well as some misplaced accusations along the way), but ultimately was eliminated from the game before his identity could be exposed.

At the time of filming The Traitors, Smedley had made appearances in Casualty and EastEnders, while she has since landed roles in Hollyoaks and Channel 4 sitcom Big Boys – with Call the Midwife now being the latest addition to her resumé.

On Instagram, she announced: "Can't believe I'm saying this: I'm gonna be in Call the Midwife, the Christmas special. Telling Dilys's story, hope I do it justice."

She continued: "One of my dream jobs thank you for having me, Call The Midwife, and thanks, Alex, my agent for getting me through the door and Sophie Parrot for casting little old me. Agh, see you on Christmas Day."

The actor shared two pictures from the episode (see below), the first of which appears to show her character in trouble, holding her pregnant belly and the hand of her young daughter, while standing in a dilapidated building.

To her left is a man holding a baby, presumably her character's husband and youngest child, while in the bottom left corner the feet of a collapsed man can be seen, suggesting this could be the site of an accident.

A second picture sees a happier moment for Smedley's character, smiling at her daughter beside her bedside as she receives care for an as-yet-unknown health condition.

This year's Call the Midwife Christmas special will be a two-parter, with fans bracing themselves for the usual blend of heartwarming moments and tear-jerking drama.

Call the Midwife returns on Christmas Day.

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