Sarah Lancashire's Black Doves role wastes her Happy Valley momentum

To be fair, I was 16 when Sally Wainwright's crime drama first premiered, and 18 when it went on a long hiatus, so I hope you'll forgive that we were merely two ships passing in the night.

Nevertheless, I can respect the enormous cultural footprint that the show made when it roared back to life: mesmerising critics, invading newspaper front pages and scoring stellar ratings for the Beeb in the process.

Lancashire herself earned no shortage of plaudits for her portrayal of Catherine Cawood, including her third BAFTA win and a special recognition award at the NTAs, where the buzzing crowd chanted her name in sheer exaltation.

While she had certainly enjoyed an impressive career up to this point, the fervour around Lancashire at this moment felt like a turning point; that things were only going to get bigger and better from here.

It's in this context that I can't help but view Netflix's spy thriller Black Doves as a slightly disappointing follow-up gig.

Don't get me wrong: the show itself is rather good. Another strong effort from underrated screenwriter Joe Barton, it introduces two compelling – and indeed, trailblazing – characters played by Keira Knightley and Ben Whishaw.

Helen (Knightley) is a loving wife and mother, who also happens to be an undercover agent for a shady organisation, while Sam (Whishaw) is an unashamedly gay assassin tasked with training her, who ultimately becomes her friend and confidant.

Their dynamic feels authentic, charming and truly fresh, which means it can't help but contrast against Lancashire's more stereotypical spy boss, Reed.

Regrettably, this enigmatic figure feels more like an archetype than a genuine human being, fitting the stern handler persona previously written with more depth for Judi Dench in the Bond films or Margo Martindale in The Americans.

Lancashire is certainly on charismatic form here, delivering Barton's dialogue with icy precision and a dark sense of humour – but we're yet to discover if there's any actual substance underneath those snappy lines.

As a result, while I praised the performance and the character herself in my Black Doves review last month, I have felt myself rapidly going cold on Reed after finishing and reflecting upon the season finale.

Over the course of the first season, we see that Reed is a strategic and ruthless spymaster, with the capacity to betray even those she supposedly cares about if it furthers her aims in any given moment.

What we don't really understand is the 'why' of it all. What could possibly have driven her to be so detached from her humanity? What motivates her loyalty to this fictitious organisation, which doesn't appear to have any overriding ethos or mission?

Black Doves has already been renewed for season 2, so it's possible that these are subjects that Barton plans to delve into further down the line. Conversely, there's also an argument that not everything needs to be spelled out.

Case in point: the harshest detractors of the Star Wars prequels are always quick to say that characters like Darth Vader and Boba Fett were more interesting in their early years, when we knew relatively little about them.

In this case, however, Black Doves delivers such thoughtful, well-realised characterisation for Helen and Sam that, by the season's end, Reed starts to feel a bit daft by comparison.

This is encapsulated in a scene from the finale in which Reed dispassionately explains the entire plot of the show to a flabbergasted Helen. The boss caps off her recap with a surprisingly sentimental comment which suggests she does have a soul after all.

But following six episodes of cruelty, betrayal and general passive aggression, it's a moment that doesn't feel earned in the slightest.

Ultimately, Black Doves' resident gangsters Lenny (Kathryn Hunter) and Alex (Tracey Ullman) show more nuance overall, despite the latter having a fraction of the screen time enjoyed by Reed.

That leads me to think that this must have been an intentional creative choice; that showrunner Barton clearly envisions Reed as an unflappable, immovable object at the centre of an otherwise anarchic underworld.

But having seen the complexity that Lancashire delivered in Happy Valley, it's jarring for her to be relegated to a role that, at present, just feels a tad two-dimensional – no matter how entertaining some of her put-downs might be.

The presence of an unfamiliar younger woman in Reed's home on Christmas Day – presumably a daughter – could well be a seed that sprouts in the second season, but for now, I'm still waiting for Lancashire's post-Happy Valley knockout role.

Black Doves is available to stream on Netflix.

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