Happy Valley star Mark Stanley has spoken out about the show's secret ending amid rumours of a fourth series.
The actor, 34, who plays depraved PE teacher Mr Hepworth, says BBC producers went to great lengths to stop the script from the series finale being leaked.
Fans were in bits after the nail-biting episode on Sunday in which fans found out Mr Hepworth had been grooming his students.
Speaking about the dramatic scenes on This Morning, Mark said: “I don’t know about the different endings but there was a lot redacted from the scripts when we were given them because they didn’t want things leaking.
“I guess things are sent through email these days and if something goes the wrong way, this seven year anticipation goes out the window."
Mark's co-star Derek Riddell, who plays Catherine's ex-husband Richard Cawood, added: “The country was so invested in it and it was so lovely to be involved in something like that.
“It seems that everybody… well you can’t please everybody at the same time but it seems most people were really satisfied with the way that it finished.”
Fans were bereft after the finale aired with many pleading for a fourth series.
Mark, who was part of a chilling sub-plot when Rob Hepworth was accused of murdering his wife in the show, admitted he saw a “hint of a fourth series” before the ending unfolded.
While much of the finale revolves around Catherine Cawood (Sarah Lancashire) and Tommy (James Norton), viewers were stunned to find out about Rob's fate.
When Catherine asked Andy Shepherd whether the teacher had been charged, he says Rob had been - "but not for Joanna, though", explaining: "We found indecent images on his phone. Turns out he was blackmailing a lad at school to send them to him."
The revelation that Rob is a paedophile came as a shock to fans, even though the warning signs were there.
Viewers found out Rob had met Joanna and formed a relationship with her when he taught at her school.
There was also that awkward scene between Ryan and and the teacher in episode 3 when we thought both characters were trying to move on with their lives.
However, Rob's lingering stare at the teenager takes on a new meaning with some viewers speculating whether Tommy's son could have been the teacher's next victim.
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