BRITISH monsters are stalking the United States, and young Americans are loving them.

A live show based on the BBC series Walking with Dinosaurs, with robotic beasts twice as high as a double-decker bus, has become a mammoth money-maker across America and Canada. The travelling show is expected to earn £50m this year, rivalling the last US tour by those other ancient Britons, the Rolling Stones.

The Australian engineers who bank-rolled the £10m show are working on a second, more advanced generation of flesh-rending carnivores and hapless herbivores to tour Asia and Europe while the originals carry on terrifying American children.

The BBC, which owns the rights to the creatures, is expected to make a multi-million-pound windfall without having to put any money into the transformation from screen to arena.

The 90-minute show is introduced by a palaeontologist who is quickly eclipsed when life-sized mechanical dinosaurs stride into the arena snarling and gnashing their teeth. A plant-eating stegosaurus is attacked by a 30ft-long allosaurus, all teeth and claws. They are both overshadowed by a 45ft-high brachiosaur.

The star of the show, however, is the tyrannosaurus rex, who is 36ft tall and 50ft from snout to the scaly tip of her tail. And she gets very irritable when two beasts threaten her 15ft-long baby, roaring at a rock concert decibel count and, at its opening shows near Seattle, scaring small children as she runs around the arena.

The dinosaurs, made of steel and latex, are operated by three controllers, one inside and two using remote controls. The leader works like a puppet master, coordinating moves with a “voodoo rig” attached to his arm.

The show, which employs 150 people, opened in Australia early this year where it sold its 300,000 seats in hours: most of its American run is sold out, despite a £100 ticket for a family of four and more for merchandise such as strap-on dinosaur tails.

Although its ticket sales are rivalling tours by rock groups such as the Stones and U2, its main rivals are children’s “stage events” such as Sesame Street Live, which contribute to a billion dollar a year industry in America.

“The kids will not be fobbed off with a second-rate show: they are very demanding customers,” said Brad Parsons, president of the Arena Network, which runs 51 giant venues in America. Parsons predicts that the dinosaur show, which recouped its initial costs in Australia, could earn £50m a year well into the future.

Tim Haines, who co-created the original documentary series Walking with Dinosaurs in 1999 and has just been nominated for a sixth Emmy television award for his computer-generated creatures, said he was “boggled” by the scale of the dinosaurs.

Nearly 800m people watched the original series, where the daily lives and deaths in the triassic and jurassic eras were brought to life by mixing computer-generated dinosaurs and real landscapes. Several spin-off programmes and books have turned Walking with Dinosaurs into one of the most lucrative and influential programmes in television history.

The reason is simple: nearly 15 years after Steven Spielberg’s Jurassic Park introduced the first photo-realistic dinosaur, children are still obsessed with the “terrible lizard”.

As seven-year-old Jose Garcia said after the opening show this month: “We love dinosaurs, they eat people.”

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