The Radio Times has announced:

" Former Doctor Who actor Peter Davison to star in Call the Midwife Christmas special

The actor will play circus ringmaster Mr Percival in the episode.

Former Doctor Who star Peter Davison has joined the cast for this year’s Call the Midwife Christmas special.

The actor, who played the fifth Doctor between 1981 and 1984, will play Mr Percival, the ringmaster of a circus which brings a large crowd to Poplar.

Davison’s other notable credits include playing Tristan Farnon in the original TV adaptation of All Creatures Great and Small and roles in At Home with the Braithwaites, The Last Detective and Law & Order: UK.

Filming on the Call the Midwife Christmas special began in August, with a detailed COVID-19 protocol policy being implemented to ensure the safety of cast and crew.

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https://www.radiotimes.com/…/call-the-midwife-christmas-pe…/