James Gray, 140 mins, starring: Charlie Hunnam, Sienna Miller, Robert Pattinson

It has been a while since we’ve had a decent film about British explorers in pith helmets roaming through the Amazonian jungles. James Gray’s brilliant new feature The Lost City Of Z (adapted from David Grann’s book) is both a throwback to an era in which rip-roaring yarns about imperial adventurers were commonplace and a story with a strong and disturbing contemporary resonance.

Gorgeously shot by Darius Khondji, it manages the feat of making the English and Irish-set scenes look just as rich and strange as those that unfold far down the Amazon. For all its epic trappings, this turns out to be a very poignant and closely focused character study of a man badly out of step in his own society, on a Quixotic journey to a destination that he knows he will never reach.

Percy Fawcett (Charlie Hunnam) has many reasons for going on his far-flung expeditions. They’re a way to redeem the family name, tarnished by the drinking and gambling of his ne’er do well father. If he is able to map Bolivia accurately, the British Empire stands to benefit. It isn’t just money and reputation that is driving him, though. He is looking for escape.

He chafes against the jingoism and racism of fellow members of the Royal Geographical Society who persist in seeing the indigenous South Americans as savages and “primitives”. If Fawcett can find the fabled “lost city of Z”, he will be able to prove that there was civilisation deep in the jungle long before Christianity was born.

Gray has a knack of giving even the most commonplace scenes in The Lost City Of Z an epic quality. The film opens in Cork in 1905 with Fawcett as a young married officer competing in a hunt for a stag. It’s a strangely morbid scene. “To death, the best source of life”, the officers toast one another as the stag is finally shot. The hunt and the ball that follows are shot with an extravagance and ambition that rekindles memories of Stanley Kubrick movies. There is lots of swooping camerawork. Costume and production design are lavishly detailed.

In these early scenes, Gray establishes that Fawcett is an outsider. He’s easily as courageous as any of the other officers but he has been “unfortunate in his ancestors” and hasn’t won any ribbons or medals. He is happily married to the intelligent and strong-willed Nina (Sienna Miller) but when he is asked to lead an expedition to Bolivia, he quickly accepts. The expedition may cost him his life. At the very least, he will be “gone for several years”. It’s one of the paradoxes of the film that, although he loves Nina, he can’t wait to get away from her.

Hunnam’s performance is intriguing. He’s an upstanding Englishman, selfless and heroic, always trying to keep his emotions under wraps, and yet he has that same zealous, obsessive quality that Klaus Kinski brought to his roles as men on mad quests in Aguirre, Wrath Of God or Fitzcarraldo. He sometimes behaves very brutally, hitting his own son and treating Nina with a chauvinistic disdain when she has the temerity to suggest that she might accompany him on an expedition. He’s a restless soul who half realises that he’ll never be able to find the lost city of Z and that, even if he does, it won’t provide the answers he seeks.

The Lost City Of Z - Trailer

Gray’s screenplay is alert to the contradictions in British imperial society. The whiskered gentlemen who have such raucous meetings at the Royal Geographical Society talk disdainfully about the poor warlike “savages” in South America and yet these tribes’ skirmishes are as nothing to the violence of the trenches in the First World War, where Fawcett commands a group of soldiers.

The debates at the RGS verge on the comical. Fawcett shows shards of pottery to try to convince his sceptical listeners that he has evidence of a lost civilisation. “Pots and pans,” they jeer at him. There’s a wonderfully harrumphing and lively performance from Angus Macfadyen as veteran explorer and Edwardian gentleman, James Murray. He’s a pompous and self-important man who insists on joining Fawcett on an expedition but is far too cowardly and unfit to last the pace.

Robert Pattinson is effective, too, in a supporting role as Henry Costin, Fawcett’s loyal follower. He gets to deliver one of the best lines in the movie. “Jungle is hell… but one kind of likes it.” Lost in the jungle, singing hymns to the natives who are trying to kill them, the British often seem very absurd but as Costin’s remark attests, they take a masochistic pleasure in their own discomfort.

The Lost City of Z Exclusive Clip

Structurally, The Lost City Of Z is very loose. At times, Gray doesn’t seem to have any clearer idea of his final destination than Fawcett himself. This is the story of three expeditions over a period of 20 years, all of them inconclusive. There’s a brutal First World War interlude too. Every so often, the narrative will lurch forward in time. When the explorers are heading down river, Gray cranks up the tension.

“We must turn back,” “there is no turning back,” characters will say to one another in scenes that evoke memories of King Solomon’s Mines. There are chases, scenes set on turbulent rapids, references to cannibalism and footage of the British explorers coming under attack from arrows and spears. The action, though, isn’t really the point. Gray’s main preoccupation is with Fawcett’s existential quest to make sense of his life.

The explorer is both a heroic figure and a forlorn and slightly pathetic one. “A man’s reach should exceed his grasp or what’s a heaven for,” a quote from Robert Browning is thrown in which sums up both the explorer’s reckless ambition and his realisation that he’ll never get where he wants to.