Happy Valley: James Norton shares backstage pictures from all series

Happy Valley star James Norton has shared a behind-the-scenes selfie with Sarah Lancashire to mark the finale of the BBC crime drama.

The actor - who plays escaped convict Tommy Lee Royce - celebrated his character's final showdown with police officer Catherine Cawood by posting a series of backstage photos from all the series of Sally Wainwright's hit show.

These included a selfie with publicity-shy Lancashire, 58, taken during filming for Tommy Lee Royce and Catherine's explosive confrontation which has been hailed by critics for its performance as well as Wainwright's writing.

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Norton, 37, also shared images of his transformation in the hairdresser's chair for the final series, in which Tommy Lee Royce had grown shoulder-length hair in prison, captioned: "New series, new look #happyvalley #bts"

Norton wrote: "Dropping some Happy Valley nostalgia before the finale on Sunday…these were taken nearly 10 years ago…"

These included a series of pictures of himself and Rhys Connah, who stars as Tommy Lee's son and Catherine's grandson Ryan, and was just eight-year-old when he made his debut in the first series of Happy Valley in 2014.

Multiple endings were filmed for the finale so that even the cast did know how the story finished.

Amit Shah, who played drug dealing pharmacist Faisal, told BBC Breakfast: "I was aware of what was going to happen to my character, but regarding scenes involving other characters - those scenes were taken out of my version of the script, so I was watching as an audience member last night."

Norton said: "I think the reason this series is particularly exciting is because everyone knows it’s the last and so everyone is going to be waiting for something to happen, and everyone is sort of predicting and guessing how Sally wants to end it.

"I have been predicting for the last seven years how she is going to end it so it was really wonderful to read the script and hear her ideas - and they don’t disappoint."

The second series aired in 2016, and the seven year wait for the final series was explained by Wainwright because they were waiting for Connah to grow up.

She explained: "I waited six years because I wanted to get to a point where Ryan would be old enough to start making choices about whether he wanted to have a relationship with his dad or not. And could he have a relationship with his dad, and how would Catherine feel about that? I really wanted to be able to explore that.

"It’s been great that we got Rhys (Connah) back to play Ryan which has been fantastic, and he has done a really lovely job in that.

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"That was always the intention, to have a gap and it has worked out just about right. Just the right period of time because he is now 16, so he can travel places by himself, he can make choices. He can do things behind Catherine’s back."

Watch: James Norton recalls his school days