*THIS ARTICLE CONTAINS SPOILERS FOR THE HAPPY VALLEY FINALE ON BBC*
Catherine Cawood (Sarah Lancashire) endured a cat-and-mouse vendetta with nemesis Tommy Lee Royce (James Norton) throughout the third and final series of Happy Valley - which returned to screens January after a six-year lay-off.
The coveted BBC saga came to a fierce conclusion at the weekend, with Catherine finally able to confront rapist and murderer Tommy, shortly before he set himself on fire.
And while many fans thought that the show's summary was fitting, creator Sally Wainwright has spoke out about the future for Catherine and her story - with her own fears as to whether the finale would do the series justice.
Read more: Happy Valley finale 'spoiled' by BBC News as angry viewers complain
The Mirror reports that speaking on Newsnight, Sally said: "I tend not to very get nervous anymore really, I'm kinda philosophical that it is what it is and people will respond how they respond."
"But I think because it appeared to be doing very well I was worried it might fall at the final hurdle and people might think it was a disappointing ending in some way but I kinda knew it wasn't. I knew it was what I wanted it to be," she continued.
"It was satisfying. I had a real choice about whether to end on a pessimistic note or an optimistic one. Which one of them was gonna survive but it was a no brainer to end on an optimistic note with someone like Catherine. She's such a force for good."
Sally revealed the ending could have been very different without the input of Catherine star Sarah. She continued: "I have Sarah to thank for that ending in many ways. I wrote the first draft and everyone seemed happy with it and she made it clear she wasn't happy with it.
"I think last Christmas, the Christmas before, [Sarah] came to my house and gave me some really good notes and pushed it a bit further and I have Sarah to thank for that."
Sally, added: "It was a great privilege to have the opinion of someone who knew the scripts almost better than I do... she was literally here all day at my house talking it through. Her performance is just off the scales."
Happy Valley fans will be disappointed to hear there's no chance of Catherine making a reappearance. She told Newsnight the third and final series is 'definitely it' and expressed the importance of 'knowing when to stop'.
However, Sally did hint at Catherine coming out of retirement one day: "Maybe she will. But we won't get to see it."
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Read next:
- How did Happy Valley end? BBC drama wraps with 'last second' death as one text changes everything
- Happy Valley fans left fuming by major spoiler without warning on ITV's Lorraine
- Happy Valley's Sarah Lancashire spoke up to 'change' ending of final episode
- Happy Valley to get extended finale as BBC confirm schedule change
- Happy Valley fans spot crucial 'clue' on Catherine's fate ahead of final ever episode
