A SPRAWLING true story of discovery at the turn of the 20th century informs writer-director James Gray’s ambitious journey into the heart of darkness.

Based on author David Grann’s nonfiction bestseller, The Lost City Of Z charts the battle between globe-trotting cartographer Percy Fawcett and the scientific establishment, who dismissed indigenous tribes of South America as ‘savages’.

In order to prove the snobbish academics wrong and anchor his place in history, Percy sacrifices relationships with his wife and children, and risks the safety of men in his care as he traces the Rio Verde upriver to its source.

“What kind of fool am I to leave my family for this place?” Percy ponders aloud, questioning the sanity of his grand expedition. It’s a question that Gray’s film never fully answers, despite thrilling sequences set in the heart of the rainforest where pottery shards seem to verify the existence of a lost city in Amazonia that predates the supposedly cultured British.

The search for answers begins in 1905. British artillery officer Colonel Percy Fawcett (Charlie Hunnam) has been ‘rather unfortunate in his choice of ancestors’. Sir George Goldie (Ian McDiarmid), president of the Royal Geographical Society, offers Percy a chance at redemption by mapping uncharted territory in Bolivia with the help of local tribesmen.

Percy accepts and abandons his wife Nina (Sienna Miller) to venture into the unknown with aide-de-camp Corporal Henry Costin (Robert Pattinson). Their son Jack (Tom Holland) is born in his father’s absence but Percy returns home with a strong conviction that he has stumbled upon proof of a lost civilisation.

A second expedition teeters on the brink of disaster, but Percy pushes forward, terrified of the consequences of failure. Shot on location in the Colombian rainforest, where cast and crew faced snakes and bouts of dengue fever, The Lost City Of Z is a handsome tribute to one man’s struggle against himself and Mother Nature. Hunnam (Sons of Anarchy) delivers one of the strongest performances of his career against a lush backdrop.

Pattinson is reserved in support, while Miller embodies an endlessly supportive spouse.

But Gray suffers from acute jungle fever expecting us to retain focus for almost two-and-a-half meandering hours. At least 20 minutes could have been cleaved from the film’s bloated frame and tossed to piranhas that swarm during one terrifying sequence.

RATING: 6/10