'Happy Valley' won't return until at least the end of 2018.

Sarah Lancashire as Sgt. Catherine Cawood

Sarah Lancashire as Sgt. Catherine Cawood

The popular crime drama hasn't been on screens since the beginning of last year and, although the show's writer Sally Wainwright has confirmed she's going to pen another instalment, fans are in for disappointment as executive producer Nicola Shindler has revealed the talented creator is tied up with another show for the BBC at the moment.

Speaking to the RadioTimes.com, she said: "We are working on a new idea for Sally for BBC1 which will be next year so the earliest 'Happy Valley' would be would be towards the end of 2018 I would suspect. She won't write the ['Happy Valley'] scripts for some time but Sally's determined to do it, Sarah's determined to do it."

However, Nicola thinks the break will do it some good as it will allow Sally to move the story on and create a new life for the remaining characters Sgt. Catherine Cawood (Sarah Lancashire), Tommy Lee Royce (James Northon) and Ryan (Rhys Conna).

She explained: "Sally is thinking about a story and the story she is thinking about literally needs time. Because if you look at the characters that are left, there is Sarah, there is James Norton and there is a young boy, who the minute he turns into a teenager it becomes a much more interesting story.

"She doesn't know what the story is yet. She is mulling it in her head but we are thinking about giving it a bit of space in story terms."

And, although Sally is yet to sit down and take pen to paper, it's believed the next series will see Sergeant Catherine - who is still grieving for her dead daughter - contemplate leaving the corrupt police force as she continues to protect her fragile grandson Ryan (Rhys) from his rapist father (James) - who is serving time in prison for raping the officer's daughter - and his conniving girlfriend.

Sally said previously: "It [the third series] will happen but it will be a little while. I have got some good ideas."