Why Stephen Graham's Peaky Blinders character is so important

"The audacity of it," says Isiah, and he's right. Dare to steal from the Peaky Blinders and there will be consequences the likes of which you've never experienced.

Prior to their travels to Liverpool, Isiah has doubts that Arthur is capable of carrying out their orders in his current state, but Ada insists that her brother's presence is vital: "No one would dare f**k with Arthur Shelby."

Tradition dictates that she's right to have such belief in her brother, even if he is suffering from a particularly nasty case of the "yamps".

Before they enter the warehouse, Arthur gives his soldiers a pep talk to ready them for battle. Referencing their immaculate attire, he growls: "Any f**king man who looks like this before, the Peaky Blinder still looks like this after."

And with that, we're treated to a classic slow motion walk as a punchy guitar riff signals the inevitable bloodletting.

"I hear there's some men here from Birmingham looking for me," barks Stagg over a strained, Dunkirk-esque score as he strides into the warehouse, the air thick with anticipation.

There's a flurry of movement as the dock workers leap from their seats to engage in combat; one of them has a metal hook in his hand that could tear someone's face clean off. But the Peaky Blinders have the upper hand after drawing their revolvers.

Things settle once more, the quiet before the storm in which guts and sinew will be splattered, Jackson Pollock-esque, as teeth are wrenched from gums and scattered like coins at the Trevi Fountain; the sound of bones being crumpled like paper bags peppering the atmosphere.

This will not end well.

But the bloodbath does not arrive. Instead, Stagg employs a tactic that is alien in a series which so often trades in brutality and bombast. His takes a hushed, almost tender approach as he undoes Arthur F**king Shelby with nothing other than his words.

"Beneath your sleeves lies the truth," he says, acknowledging Arthur's addiction. "The marks on your arm."

Stagg doesn't so much look at him as peel back the bravado and stare directly into his soul, removing Arthur's sting with naked truths that are both confronting, but also laced with empathy. Stagg was once where Arthur is now following his service in France, where he gained a taste for morphine, and he uses that shared experience to humanise Arthur in a way that few ever have – and certainly never during a moment of conflict, which is a first for the series.

Stagg notes that he, too, sought solace in Christ, but was unable to find peace. He talks of love lost – Arthur hasn't spoken with his wife Linda in years. Like his own father, he has failed to be present for his own kin.

He once thrived in such scenarios, wielding his razor blade-stuffed flat cap with vim, but Stagg's ability to disarm him showcases the sea-change within Arthur. Perhaps his former address to Isiah et el was for his own benefit rather than theirs.

"Don't build a mountain," says Stagg. "Walk like it's a flat plain, easy step by easy step."

He exposes his own vulnerabilities while extending compassion to Arthur, which is a combination the Shelby mad-dog is unfamiliar with, but in need of, and it's that piece of counsel that prompts Arthur to order Isiah and co to stand down.

Showrunner Steven Knight hinted at that outcome with the use of Idles' Kill Them with Kindness, the song which played as the Peaky Blinders made their entrance into the warehouse.

"I'm guessing it is hard for you to see that empathy will cut down your throne," reads one of the lyrics.

It should also be noted that the casting of Graham, who has achieved national treasure status, also lends itself to a performance which is less geared towards villainy, à la Jimmy McCavern or Father John Hughes, and allows him to tap into the sincerity and soulfulness that has endeared him to the public. In a series where we're encouraged to root for the Shelby family's continued survival, it would be a challenge to market Graham as an antagonist.

It's not unusual for Peaky Blinders to yank the rug out from under viewers, but this felt especially unforeseen. We were gearing up for conflict, with Stagg's fate a foregone conclusion. He dared to steal from the Shelby Company Limited – a bold move that has resulted in paralysis or death for so many who have come before. But what played out subverted expectation entirely, unveiling the true extent of Arthur's collapse and further emphasising that much of this season, up until this point, has been a quieter affair.

It's not clear what the rest of the series holds for Arthur following this latest development. He is clearly not the man he once was, with his position in the family business now cloaked in uncertainty following this latest debacle, which begs the question: where does he go from here?

There's a finality to Arthur's arc, which feels apt given that Peaky Blinders is on the homestretch, but whatever lies in store for him, it's safe to say that he'll be spending plenty more time locked away in the company safe first.

Peaky Blinders continues Sunday 20th March on BBC One and BBC iPlayer, and seasons 1-5 are also available to stream on Netflix. Read our guide to the best series on Netflix, check out our Drama hub for more news, interviews and features or find something to watch with our TV guide.

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