Why do some women wear chunky shoes and gloves? Because they are witches who are trying to hide their distinctive toe-less feet and cat claw fingernails. What would happen if you weren’t able to satisfy your need to read books? You would develop the power of telekinesis with which you could get your own back on your terrifying head teacher and rotten family. Where do dreams come from? A Big Friendly Giant (BFG) catches them in Giant Country, bottles them up, and then creeps through the streets in the dead of night and blows them in to the windows of sleeping children and adults through a long trumpet-like instrument. Obviously.

Herein lies the mastery of Roald Dahl’s storytelling; the unrivalled ability to play to children’s curiosity – and fears – and provide answers to questions that, while seemingly absurd to adults, make perfect sense to small enquiring minds. It is reassuring, then, that Steven Spielberg, with a pedigree for directing family-friendly adventure movies, takes the helm of this two-hour CGI-infused adaption of Dahl’s 1982 bestseller The BFG.

John Williams, as ever, provides a brilliantly emotive score that is in perfect sync with Spielberg’s direction and Melissa Mathison’s screenplay. The BFG’s protagonist Sophie (Ruby Barnhill) – a curious and stubbornly independent girl who resides in a London orphanage following the death of her parents when she was a baby – finds herself whisked away to Giant Country with a 24-foot-tall giant (recent Oscar winner Mark Rylance) whose job it is to catch, mix, and distribute dreams to the young and old while they sleep.

A friendship soon forms between Sophie and the BFG – Sophie’s steely determination complementing the beaten-down dejection of the giant – who find common ground in a shared sense of loss and isolation. All of this is set against the threat of a throng of nine man-eating giants, led by The Fleshlumpeater (excellently voiced by Jemaine Clement), who are intent on sniffing out Sophie and gobbling her up.

Fans of the book will be pleased to know that the BFG’s language is rightfully delightful; "[Words have been a] twitch-twickling problem to me my entire life", he laments, though his unique and creative grasp of English provides many chuckle-worthy moments in the film. Snozzcumbers – a slimy, squelching, pustulous marrow-like vegetable on which the BFG is forced to subsist – also make an early appearance. But the undoubted standout of the film is the impressive visual effects, which prove to be a real treat on the big screen; Mark Rylance’s motion-capture performance is so convincing that you can hardly tell where the special effects end and Rylance’s superb acting begins.

Great care has clearly been taken to create a believable fictional world, none more so when, under nightfall, the BFG takes Sophie to Dream Country to show her where dreams come from. The result is a beautiful and magical scene that is sure to delight all audiences. In its loyalty to the original plot, however, the to-ing and fro-ing between Giant Country and London gives the film an uncomfortable pace. Consequently there are aspects of the story that feel underdeveloped; the blossoming friendship between Sophie and the BFG isn’t always completely convincing, and the gruesome nature of the other giants’ activities is glossed over.

It’s also unfortunate that the joys of frobscottle and whizpopping – which feature prominently both in the book and the 1989 TV animation – are relegated to two fairly brief appearances (though the second appearance, set in Buckingham Palace, provides the biggest laughs of the film). The downside to this is that the film may struggle to elicit a strong emotional response from its audience, however, children are unlikely to notice or mind, as they will they be captivated by the absolutely wonderful visuals. Some adults – especially those burdened with childhood nostalgia for the book – may be left feeling underwhelmed, but, ultimately, the film carries a nice message surrounding the power of dreams and friendship, and the amazing CGI elevates The BFG to something that is enchanting and memorable.

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