Only Stephen Graham can save this plodding final series of Peaky Blinders

Stephen Graham is exactly what Peaky Blinders (BBC One) needs as it tries to shrug off the gloom that has accumulated around this stodgy farewell season of flat-capped Brummie noir. Graham could look scary playing a fairy – which is exactly what he did in 2019’s Hellboy (albeit a Celtic fairy with magical boar tusks). So he was in his element as he made his Peaky Blinders debut, dusting himself down from a five-a-side kick-about in a docklands warehouse in Liverpool to square off against a feral Arthur Shelby (Paul Anderson).

Because it’s Peaky Blinders, where even the milkmen are invariably named after figures from Greek mythology, there was never any prospect that Graham’s character would go as John Smith or Oliver Inconspicuous. We were introduced to “Hayden Stagg”, which actually sounds a bit like a Celtic fairy with magical boar tusks, and he was, of course, a coiled fist of barely suppressed menace.

Stagg works as union convener (apparently a fancy term for shop steward) at the docklands lockup where the Shelbys’ opium reserves were stashed. His men had been helping themselves to the supply. This prompted Ada (Sophie Rundle), temporarily in charge of the family business with Tommy otherwise occupied, to dispatch Arthur and sidekick Isaiah Jesus (Daryl McCormack). A stern coshing was on the cards.

Our first peek at Peaky’s latest antagonist was a fleeting affair. Yet even with limited time, Graham left an impression. Just as in The Irishman and Line of Duty, he seared himself into the action with a few lines of dialogue and a burning glare.

Stagg might have locked horns with Arthur but he clearly understood the impossibility of overcoming the Shelbys by force. Instead, he used psychological warfare to creep beneath Arthur's skin, grey as a cadaver as he fought opium withdrawal. Just like the poor, shivering Shelby sibling, Stagg revealed that he too had once been a morphine user. And he understood Arthur’s pain. However, he was also proof that you could beat addiction. A very Peaky Blinders sort of self-help guru.

The stand-off was the best thing in an episode that felt like filler, even though it ended with a life-changing tragedy for Tommy (Cillian Murphy) and Lizzie (Natasha O’Keeffe). Poor little Ruby had consumption, though when the moment of death came Tommy was nowhere to be found.

He was half way up the mountains with mystical sister-in-law Esme (Aimee-Ffion Edwards). They were trying to lift the “gypsy curse” from which Ruby supposedly suffered. And which something to do with that malignant sapphire from season three.

This was awfully drawn out. Tommy and Esme spent forever huffing about in the wilderness. Exchanging arch, florid dialogue, they sounded like characters from the Nick Cave Murder Ballads album. You half-expected Kylie Minogue to float by in a funeral shroud.

As their horses plodded, so did the pace. So when Arthur and Stagg had their face-off it was as if the series had briefly stirred from a stupor. Reeling from the death of Helen McCrory (Aunt Polly), Peaky Blinders continues to slouch forward rather than stride confidently into the sunset. We can only hope that when Cillian Murphy and Stephen Graham finally share the screen, sparks will fly.