Gangs of New York is in many ways Martin Scorsese’s most ambitious film but it is also his most undisciplined. This is an example of filmmaking gluttony, of an artist given leave to indulge himself to the extreme without being held back. In certain respects Scorsese’s attention to detail is admirable but this isn’t a documentary; it is a work of narrative fiction and sometimes it seems to forget that, much to its peril.

The film begins in 1846 in Manhattan’s rough Five Points district, where a war rages between American born residents who refer to themselves as the Natives and are led by Bill “the Butcher” Cutting (Daniel Day-Lewis), and Irish immigrants who call themselves the Dead Rabbits and follow Priest Vallon (Liam Neeson). The two sides face off in a bloody, no holds barred fight that is edited together like a music video – the first sign that the film is going to run itself off the rails. Cutting delivers the death blow to Vallon and outlaws the Dead Rabbits, an event witnessed by Vallon’s son, Amsterdam, who is then taken away to an orphanage.

Sixteen years later Amsterdam (Leonardo DiCaprio) returns to Five Points, determined to avenge his father. He ends up in the employ of Cutting – no major feat; everyone in Five Points works for Cutting one way or another – who is unaware of his relationship to Priest Vallon and eventually comes to look on him as a son. The relationship between Amsterdam and Cutting is the most interesting part of the film, giving dimension to both characters and providing the foundation for the story as a whole. As he’s taken under Cutting’s wing, Amsterdam inadvertently finds himself growing closer to the man who murdered his father and actually protects him at one point by preventing someone else from killing him. Eventually Amsterdam does pull himself out from under Cutting’s spell and makes an attempt on his life, an attempt that is thwarted by Cutting and which renews the Five Points gang war that has always been simmering just beneath the surface. Running parallel to this is an examination of the larger scale conflict between wealthy Americans and the poor immigrants who step off the boat and, essentially, into uniform to fight the Civil War. The conscription of new citizens creates a veritable powder keg in and around New York, eventually exploding the city both literally and figuratively.

If this was all that there was to the story it might work, but the film adds another layer through the character of Jenny Everdeane (Cameron Diaz). Jenny is a master pickpocket who has a past with Cutting and is, inevitably, a love interest for Amsterdam. I have nothing against Diaz as an actress – her accent here is shaky, but so is DiCaprio’s – but the inclusion of this character, particularly in so prominent a role, is a really a narrative indulgence. Amsterdam’s relationship with Cutting is fraught enough without putting Jenny between them, and Amsterdam’s romance (if it can be called as much) with Jenny simply pads the film, swelling it to gargantuan proportions. There is nothing about this part of the plot that is necessary and one must think that it is included on the assumption that all films need “a girl” in order to appeal to as many potential viewers as possible.

If the narrative focus weren’t already significantly diverted by the numerous plot lines, the film’s attention to historical accuracies might drive one to distraction. The detailing is extraordinary, giving the film texture, but the art direction, costume design and all the small things are treated so lovingly that the setting becomes more interesting than most of the characters. Scorsese’s desire to fully recreate the world of Civil War era Manhattan is admirable – the construction of massive sets in Italy is reminiscent of the old Hollywood filming style, particularly D.W. Griffith’s Intolerance - but so much thought seems to have been put into the background that it makes the problems in the foreground all the more apparent.

There are, however, many good things about this film. Individual sequences work very well, particularly the finale. The Natives and the resurrected Dead Rabbits meet for a final showdown, apparently unaware that the city is about to erupt due to conscription related riots. As they prepare to face off, the Navy starts firing cannons into the city to quell the rioting and the infantry marches in, gunning unruly New Yorkers down. This moment was supposed to be the defining battle of the Five Points gangs, the event that settled once and for all control of the district, but Amsterdam, Cutting and all their followers have failed to realize that their way of life is already being left behind as the world transforms around them. There’s something almost poetic about the way the cannon balls sweep through the gangs, effectively ending decades old animosities in a second. Sequences like this one show what Gangs of New York could have been if only someone had stepped up to reign it in a bit.

Watch a trailer for the film here: