Lighters up, tissues at the ready.

Coached by their father Jack (Holt McCallany), brothers Kevin (Zac Efron), David (Harris Dickinson), Kerry (Jeremy Allen White) and Mike (Stanley Simons) are pushed to become a wrestling dynasty. Jack's domineering attitude clashes against his sons, all of whom are eager for his approval but protect one another. However, as their careers progress, the brothers are rocked by unimaginable tragedy, giving rise to the belief that the family itself is cursed...

It's no longer an open secret that wrestling as a form of entertainment has come from a murky past. Notwithstanding the recent allegations surrounding Vince McMahon, wrestling has always come with an inherent darkness beneath all the chintzy glamour and show business. The mere fact that there's a dedicated Wikipedia article to premature wrestler deaths speaks volumes. 'The Iron Claw', however, isn't a wrestling movie - or even a sports movie, for that matter. The Von Erichs could just as easily have been a family of musicians, doctors, train drivers - anything at all. Wrestling is merely the framing device for a powerful and moving examination of masculinity, both toxic and positive, and what it means to be a brother and a son.

From the black-and-white opening sequence, we're introduced to the world of wrestling as one of pain, grit and hardship. We see Holt McCallany's character dominating an opponent with the titular submission hold, forcing his will down on another man and foreshadowing how he will eventually crush his own sons into submission. Yet, in spite of that, he greets his then-young family warmly and leaves the performance behind. The movie jumps forward to the seventies, where the sons are on their way in their respective careers, though not without the father's single-mindedness pushing them along. He openly talks about how he ranks his sons, with Jeremy Allen White's character being on top as he's on his way to becoming an Olympic medal-winning athlete, while Stanley Simons is placed last, owing to his talent with music and unwillingness to bulk up and wrestle like his brothers.

There are sharp strokes and pops of colour to make each of the brothers distinct, instead of a blur of frizzy hair and ridiculous muscles. Zac Efron's Kevin, very much the core of the movie, is painfully shy around women and softly spoken, described later by his on-screen love interest Lily James as a "sweet, sweet man". Harris Dickinson's David, on the other hand, seems comfortable on the mic is by far the most naturally gifted of the brothers. Jeremy Allen White, meanwhile, is taciturn and intense, while Stanley Simons is more of a wisp of a presence. Holt McCallany, meanwhile, is chiselled from granite. What is clear from the movie, however, is how their bond is unbreakable and how much they clearly survive together.

Outside of these, however, we find that other characters aren't quite as clearly drawn, and it's often to the movie's detriment as it leaves out an important point of view. Both Lily James and Maura Tierney are entirely underutilised, and although it's a movie about brothers and fathers, there's something in effectively ignoring the two women who had the most impact on the characters of the story. This, of course, is very well be the reason for their troubles, and by their constant need for competition and success, it drives away any chance of being normal or happy.

Sean Durkin's script and direction tells a story that is both operatic and deeply human. There's almost a Richard Linklater quality to some of the early parts of the movie, wherein we see the brothers just hanging out and enjoying each other's company as it slips into a breezy hangout movie, before jumping into an energetic wrestling sequence set to the likes of Rush or Blue Öyster Cult. Indeed, the whole movie feels like it could be the inspiration for an eight-minute power ballad by one of them. Later, as the story turns towards tragedy, it moves into deeper psychological depths and utilises wrestling to wrap itself around it. Ric Flair even turns up as a sort of final battle with masculinity itself at one point. Wrestling aficionados will no doubt be aware of the full extent of what happened to the Von Erichs, and while 'The Iron Claw' does dial back and omit certain elements, it's shown as it happened for the most part.

The final moments of 'The Iron Claw' are particularly painful, and although Zac Efron's performance throughout the movie is moving, he truly outdoes himself here with a sincerity that is awe-inspiring and undeniably emotional. We have a word for those who have lost a spouse, parents, or children - but none for those who have lost a sibling. Whatever the word is, whatever the name of that pain is, 'The Iron Claw' captures the beauty of the bond of brothers, and how far down it goes to break a soul when it's gone.

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