Worzel Gummidge, the popular and kind-hearted scarecrow character in British children’s fiction, will return to screens this Christmas with a strong and unapologetic message: protect the environment.

A children’s television classic since Jon Pertwee portrayed him on ITV between 1979-81, Worzel, the nattily dressed scarecrow of ten acre field, has been rebooted for BBC One by the writer and actor Mackenzie Crook.

Two lavishly made one-hour specials will be shown in prime slots over Christmas aimed at the whole family.

Crook said he saw the character as a “guardian of the natural world” and the programmes were an opportunity to write something which was, he hoped, very funny but did have environmental messages. “Hopefully it is very subtly done, not in a preachy way. I don’t want it to be annoying.

“Kids are so on board with that [environmental] message at the moment, it’s the adults that are catching up. It seemed natural,” he said.

‘Warm, friendly and extremely silly’ Worzel Gummidge will be shown on Boxing Day and 27 December. Photograph: Amanda Searle/BBC/Leopard Pictures

The two episodes touch on the consequences of the climate crisis as well as plastic pollution. Crook said: “It seems to be the easiest, most visible thing we can start doing, just not using single-use plastic. I can see even in a year or two it will be banned and we won’t be able to believe that we were able to use it.”

The programmes do have serious intent but they are also very daft and will appeal to both children and adults. Sir Michael Palin, who plays the Green Man, the creator of all scarecrows, saw the programmes as an “oasis of calm … it is also a lovely oasis to be in because it is warm and friendly and extremely silly”.

The programmes are markedly different in tone to so much that is on television at the moment, he said. “It’s usually in your face, fast, high action, noisy … this is calm and you have to listen, take it in and I think the more TV like that the better, really, otherwise we’re just getting everyone shouting for attention.”

Vicki Pepperdine plays a mean Aunt Sally. Photograph: Amanda Searle/BBC/Leopard Pictures

The films will be shown in the evening on Boxing Day and on 27 December.

The creatives who worked with Crook on his BBC Four show Detectorists have teamed up with him again for Worzel Gummidge. The cast includes Steve Pemberton and Rosie Cavaliero as a farming couple who take in two foster children and quickly learn there is more to the wooden scarecrow in the field than meets the eye. Zoe Wanamaker plays an eccentric aristocrat and Vicki Pepperdine plays Aunt Sally, which is a very different role to the one played by Una Stubbs 30 years ago. She is definitely not a love interest.

Another difference is that Crook’s Gummidge does not have interchangeable turnip and swede heads. He has one, which is made of wood. His brain is made from conkers.

Worzel Gummidge was created in the 1930s by the novelist Barbara Euphan Todd and the first book was published in 1936.

“It is an enduring story of fish-out-of-water kids who find a secret and magical friend who leads them on adventures,” said Crook.

The books are “of their time but the world and the characters are still there so we brought it up to date and made our own stories”.

Crook said he hopes there will be more Gummidge to come. “Adapting Barbara Euphan Todd’s books into these two films has been a joy and I’ve completely fallen for her charming, irreverent scarecrow.”