Blue Lights season 4 review: Another explosive run of this BBC drama

Blue Lights has something of the Mission: Impossible fuse about it. Each season of the BBC drama feels as though it begins with a match being struck, and it’s our job to follow the sparking trail and anticipate the detonation. Only, in this fourth run of the Belfast-set procedural, there’s barely time to watch that flame take hold before everything blows apart.

The flashpoint is a migrant resource centre, where loyalist anti-immigration protesters, a sea of Union flags behind them, livestream their demonstration. Tapping into a feature of the current news cycle, we then see just how frighteningly quickly a crowd can be mobilised through social media, with participants often concealing their identities behind face masks.

A sudden influx of republicans, galvanised by tricolours, leaves the police fearing they’ll be overwhelmed. Those worries prove well-founded, as officers including Grace (Siân Brooke) and Stevie (Martin McCann), along with a tactical support group ostensibly protected by helmets and riot shields, soon find themselves facing an onslaught of fists and flying rocks.

A slow burn, this most definitely isn’t. But once the dust settles, the plot pivots, and what initially looks like a discourse about asylum morphs somewhat awkwardly into something else entirely: a story about the consequences of being exposed. Thanks to the actions of rabble-rouser Katie (Tabitha Smyth), who makes a scarily rash move online, Grace is left realising how a few digital taps can become a very real threat to someone’s safety – in this case, her own.

And the prospect of having things laid bare gradually emerges as a fear hanging over almost everyone, whichever side of the law they’re on. As Grace worries that she’ll become a target after her name and service number are shared among Katie’s followers, ever-present crime boss Tina McIntyre (Abigail McGibbon) starts to fret that son Mo (Michael Shea), whose nerves are fraying badly, will lose it on the stand as he finally faces trial for the joint-enterprise killing of PC Gerry Cliff back in season 1.

What Tina envisages is the truth about the McIntyres’ involvement with MI5 spilling out if a guilt-ravaged Mo runs off at the mouth. But neither Tina’s instinct for self-preservation nor the security service’s determination to protect its own secrets ought to be underestimated.

The manipulation of truth becomes a feature both inside and outside the courtroom, with justice potentially becoming collateral damage. And as for the grievances over cultural identity and social cohesion that preoccupy the likes of nativist Katie, there may be a hidden hand at work here, too – one quietly fanning the flames of outrage and harassment.

Haunting these legal scenes is the still deeply missed Gerry, whose final moments appear in CCTV footage being played to the jury. But thanks to a special flashback episode, we’re subsequently treated to a full hour with actor Richard Dormer, whose voice really ought to be used to test a sound system’s bass settings.

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Given that Blue Lights has only ever depicted the latter part of Gerry and Sandra’s (Andi Osho) marriage, followed by the grief of his death, it feels almost miraculous to witness the fledgling moments of their relationship in the decidedly unromantic setting of full-on public-order training, complete with Molotov cocktails.

It’s an opportunity, too, to discover the roots of the darkness that cloaked Gerry’s career and the piercing reason why he remained a response officer for so many years. And it’s in this specially filmed throwback that the overarching theme of this fourth season – which, up until this point, has felt a little baggy and loose – suddenly comes into sharper focus.

Thanks to information that Gerry hands to Sandra before his death, both we and the officers at Blackthorn police station begin to glimpse the unseen force that has been controlling, interfering with and manipulating events from the shadows.

Only five of the six episodes were made available to critics ahead of broadcast, but the penultimate hour sees Sandra weighing what she should do with the data at her disposal. Others back at the station are also growing tired of having the wool pulled over their eyes by people determined to keep things buried and their reputations intact. After pooling their knowledge and airing their grievances, a plan of action is formed.

And suddenly, another fuse is being ignited. With Sandra and her colleagues finally resolved to reveal all that they know, those assiduously guarded truths may end up exploding with a force that’s brutal and scarring.

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