Blue Lights season 3 is still top-tier drama – but there's a problem emerging

The reason Blue Lights stood out is two-fold – firstly, there's its sense of place, with a real authenticity surrounding its portrayal of policing in Belfast.

The other was its characters and their interpersonal dynamics. Brought to life deftly by a supremely talented cast, these characters felt fully fleshed out and recognisable from reality, with their relationships – whether friendly or romantic – something we could really buy into.

Now in its third season, those things are all still true. In fact, in many ways, they are enhanced. We know the characters better than ever now, so care more about them, and they can be put into more situations we know are a challenge for them individually.

It's great to see them back on our screens, fighting the good fight and helping to protect the peace, one case at a time.

However, watching this third run of the show I couldn't help but notice something wasn't quite right. It wasn't anything substantial and it didn't make the new episodes in any way unwatchable. In fact, they are still a whole lot better than plenty of the dramas on TV right now.

Still, it's a problem which still feels as though it is emerging, one which could grow into a bigger and bigger detriment as the series continues – and it's simply one of overstuffing.

When Blue Lights started out, we had three main protagonists – Siân Brooke's Grace, Katherine Devlin's Annie and Nathan Braniff's Tommy.

Sure, Martin McCann's Stevie was always a major player, as were Joanne Crawford's Helen and Andi Osho's Sandra. There were always some strong supporting characters, and it was the group dynamic which one of the key selling points.

But the reason the three were so cemented as our leads was that they were all rookies starting out on their journey. They shared a common experience, a common goal, and we were getting established to this world fresh, through their eyes.

As the series has progressed with them, they have naturally blended more into the team, meaning other characters have taken on greater prominence alongside them. We have also gained major new additions along the way, like Frank Blake's Shane and Dearbháile McKinney's Aisling, while season 3 introduces Michael Smiley as another key figure, Paul 'Colly' Collins.

In one sense, the more the merrier. All of these characters have something new to add, and provide additional perspectives that help to flesh out the world of the show.

However, it's clear from season 3 that creators Declan Lawn and Adam Patterson are keen to provide substantial stories for each of them, and that's where the problem starts to emerge.

Each season has only six episodes to fill, six hours for Lawn and Patterson to tell their stories. In season 3, you can start to see these jostling for time, attention and weight, a factor which is exacerbated by a lean towards darker, more emotionally involved storytelling.

While speaking with Radio Times, Devlin noted that this season features some "really, really heavy topics" and "really, really heavy scenes", and she's not wrong.

Annie's storyline in particular is heartrending this time around, and stunningly portrayed by Devlin, but all of them go through the wringer. Grace's storyline is moving, raw and personal, as is Aisling's, as is Tommy's. That's to name but a few in an overall tapestry that is somewhat bursting at the seams.

Of course, the series wants to have its cake and eat it too. Just because it's tackling heavier topics, and a lot of them, doesn't mean it doesn't want to have a pretty broad new villain played by Cathy Tyson, plenty of call-backs to previous seasons, some light-hearted bantering moments and a larger storyline setting up elements for season 4.

This is all good and proper – in fact, more of all those latter elements would be welcome. Unfortunately, the balance still feels somewhat skewed towards the darker stories and more bombastic moments, meaning the quieter, lighter moments between the characters are rather lacking this time around.

It can leave the season as a whole feeling somewhat bleak and overwhelming, with disputes, emotional heft and heartache coming from all angles.

When it comes to the more propulsive, plot driven elements of the show, one can't help but feel that its two-season renewal has had an impact here.

By the end of the season, some elements of the story are wrapped up here, but there are so many teases towards the future and what's to come next that it's easy to lose track.

It appears that Lawn and Patterson have decided to lean into the extra time they have now, and set more things up than they are willing or capable to deal with at this point. This always feels like a risky move, as you never want a full season of TV to only feel like half of a whole, a tease for something else yet to come.

Blue Lights never quite indulges itself that far, but if you're left scratching your head at the end of the finale, trying to work out how many threads have been left running and how many have been wrapped up fully, in a satisfying manner, you won't be the only one.

Once you've finished watching season 3, it's hard not to look back at the vast majority of individual scenes, individual character journeys and individual storylines and feel that you have been watching some superb drama.

The cast are as stellar as ever, and the scenarios the characters are put in remain deeply engaging.

However, taken as a whole, the season itself does feel slightly knotty, a bit messy and, at times, overwhelming. An imbalance has started to set in, both structurally and tonally.

It's nothing that can't be easily rectified, but as the series continues to grow and expand, it's something that could easily get out of hand, and lead Blue Lights astray from the phenomenal and intensely watchable drama it started out as.

Blue Lights season 3 is available to watch in full on BBC iPlayer now, and airing weekly on Mondays on BBC One.

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