For the past six weeks, it has felt as if the country has stuck to the exact same Sunday routine. First, we wait until 9pm, then we put Happy Valley on and all stop breathing for an hour. The sheer amount of dread writer Sally Wainwright has managed to pack into each episode of Happy Valley’s third and final series is staggering. Unless Wainwright is setting us up for the mother of all anticlimaxes, the series looks as if it has all been leading up to one final confrontation between Catherine Cawood (Sarah Lancashire) and Tommy Lee Royce (James Norton). They are each keen to move on with their lives by escaping abroad – Royce to Marbella, Catherine to the Himalayas – but it would be foolish to assume that both of them will get to the end credits alive. If by some miracle they do, it’ll be time to fear the worst for Ryan (Rhys Connah), the troubled boy at the centre of their tug of war. The whole thing has been terrifying. However, this isn’t necessarily the reason why Happy Valley will be remembered as one of the UK’s all-time great TV dramas. No, for all the fear and violence and foreboding, Wainwright’s genius has been to shoot Happy Valley through with all manner of small, warm, human moments that counterbalance the nastiness elsewhere. The best example of this is the line about stew. A moment of television so perfect it should be cordoned off and independently handed as many awards as possible. Catherine spends the scene trying to explain to Ryan that Royce – his biological father – is a psychopath of limitless evil. “He has a kink in his brain,” she tells him. “A twist, a psychological deformity. It’s an absence of something.” Eventually, Ryan tells her his tea is getting cold. She asks what it is. “Stew,” replies Ryan. And Catherine, as she tries to stop the person she loves most in the world from sliding towards evil, stops to consider the reheatability of his tea. “That’ll be alright,” she sniffs. Other examples run through the series like fat through a steak. The scene in episode one, where Catherine explains her desire to drive to the Himalayas, is probably the biggest red flag yet that an unhappy ending is waiting for her. But Wainwright managed to conceal the terror of the moment with a long digression about a yoga class, where several police officers farted so violently that “Greta Thunberg had to come and speak to us”. And that lovely scene in episode four where a great big chunk of potentially boring exposition is broken up by Catherine casually telling her ex-husband that the mechanic working on her Land Rover had been in jail for killing her son. This is what sets it apart from, say, Line of Duty. Both shows are relentlessly propulsive, plot-driven beasts that require the momentum of a galloping narrative. But where Line of Duty achieves this with long expository scenes that usually come at the expense of character development, Happy Valley is smart enough to fill every conversation with petty little chides and mixups that ground everyone in an easily identified reality. In the most recent episode, a murder scene was spied upon by the family of the murderer. As tense as it was, it was still undercut by an ongoing feud about grammar. “One of them private hearses is going in!” yelps one of Faisal’s daughters, as she watches a black van pull up. “One of those private hearses,” tuts her mother. Occasionally, rather than just fleshing out a character, these details actually further the story – like when Catherine realises Ryan hadn’t defaced his teacher’s car with obscene graffiti because “I’ve seen how you draw a cock and balls when we play picture consequences, and it’s nothing like that”. For the most part they’re emotional beats, either there to reinforce the authenticity of the show (it’s staggeringly rare to find a series where people actually talk like people), or to act as weird little touches of affection from characters who aren’t very good at expressing themselves. Especially this series, Catherine has been increasingly difficult to rub along with. She’s furious and obsessed, and determined to push those closest to her as far away as possible. She’s clamped down so tightly that, in the hands of a less talented writer, she could quite easily tip over into becoming a monster. But Wainwright’s little grace notes – the stew line, the disappointed “Really?” as she finds a lighter in Ryan’s pockets – are enough to show us that she’s still giving what she can. Time and time again, these flourishes demonstrate just what a spectacularly written series Happy Valley is. We should be sad that it’s going away, but we should be absolutely thrilled that Sally Wainwright isn’t.