Even children who fear monsters love dinosaurs. From Ian Beck’s Tom and the Island of the Dinosaurs to the gloriously rollicking Dinosaur Stomp and films such as Jurassic Park, they are big and hungry, and beastly fun. For years, Cole has been a bit of an unsung hero of children’s fiction with his Astrosaurs series about dinosaurs in space, an idea so funny that many 7-9s cannot help but read them.

Z-Rex is a bit of a departure, however, in being simply a terrific thriller that younger fans of Anthony Horowitz will love. Adam, 13, like so many teenage boys, is interested in little but playing virtual-reality games — which explains why, when his computer scientist dad disappears and a very real, genetically engineered T. rex bursts out of a secret laboratory in Santa Fe, Adam doesn’t react quite as expected.

Alone, with neither passport nor money, pursued by sinister armed men and in an alien culture, Adam has only his father’s mobile phone and his bike to get him out of trouble. In short, adrenalin-packed chapters he finds himself searching for his father while the runaway dinosaur is initially no more than a “thick black shadow” overhead, dropping cream-coloured convertibles on his enemy. How can Adam get back to Edinburgh? The answer: to team up with a talking, flying, man-killing monster that could crush you with a flick of its talons.

The alliance between boy and dinosaur is depicted with energy and an engaging sense of the possibilities of an interspecies partnership. It’s a romping read, with an original twist and lots of suspense. Yet the premise may sound familiar if you substitute a dragon. From Carole Wilkinson’s Dragonkeeper trilogy to Lucinda Hare’s debut of the same name, befriending dragons is a modern child’s dream.

Cressida Cowell’s latest instalment in the adventures of the weedy Viking nerd Hiccup Horrendous Haddock III, How to Break a Dragon’s Heart, maintains the standard of the previous seven books. With the girlfighter Camicaze kidnapped by the fearsome Berserks, and Hiccup’s best friend, Fishlegs, facing certain death for sending love poems to the daughter of Ug the Uglythug, the quest becomes particularly dangerous. That’s even before Hiccup’s old enemy Alvin the Treacherous pops up again, minus yet another limb.

These are glorious stories in every way, though the opening will confuse those unfamiliar with Cowell’s claim to be translating it all from Old Norse. The witty artwork is enough to keep any child of 7+ engaged, but its narrative sophistication makes it fun for teenagers, too. Many strands of previous plots come together so that we discover just why Hiccup can speak to dragons, and what kind of things his lazy, cowardly but utterly adorable little dragon, Toothless, has been greedily swallowing. The jokes about thuggish behaviour, hysterical nutters and stupid heroes are underpinned by a good deal of wisdom concerning the nature of true courage — it’s no surprise that next spring, the animated film of the first Hiccup book, How to Train Your Dragon is emerging from DreamWorks, the team that made Shrek.

Z-Rex (10+) by Steve Cole (Doubleday, £10.99; Buy this book; 281pp)

How to Break a Dragon’s Heart (7+) by Cressida Cowell (Hodder, £5.99; Buy this book; 310pp)

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