The programme is a new adaption of the HE Bates novella The Darlings Buds of May, which was previously made into a hit series of the same name in the 1990s starring David Jason and Pam Ferris.
Walsh will star as Sidney 'Pop' Larkin while Scanlan portrays his wife Florence 'Ma' Larkin, characters formerly played by Jason and Ferris respectively.
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The new photo shows Walsh sporting sideburns while both wear period dress for the series set in the 1950s.
The programme will follow the Larkins, their six children and the family's escapades in the Kent countryside. While kind-hearted and good natured, the family have a disinterest in authority.
Bridgerton star Sabrina Bartlett is taking on the part of their eldest daughter Mariette, first made famous by Catherine Zeta Jones in the 90s series.
Her love interest Cedric 'Charley' Charlton, who arrives in the village to investigate the Larkins' tax affairs, will be played by Tok Stephen.
Also among the cast is Walsh's son Barney Walsh who is set to play local copper PC Harness.
It's written by screenwriter Simon Nye whose credits include The Durrells and Men Behaving Badly.
When the series was announced last year, The Chase host Walsh said: "I’m thrilled to be asked to be part of this much loved and iconic series of stories.
“The warmth and affection that HE Bates has generated through his books is so uplifting and I cannot wait to be part of the Larkin family. It’ll be a hoot!”
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