The boundaries between fiction for the young and what we might call ‘adult’ fiction are blurry. The publisher David Fickling once said that there’s no such thing as a children’s book – only good books that can be read by all. Mal Peet, who died last year, wrote books that certainly fit into that category: his prose is stylish, his imagination expansive and original and his stories heartfelt. His friend Meg Rosoff has completed his final manuscript and the result is Beck, a searing bildungsroman about a mixed-race Liverpudlian boy heaved off to Canada in the early 20th century. All the abuses of the world are hurled at him: he is molested by priests, whipped by ignorant farmers and wanders the wide, lonely wastes until he meets someone who might finally be able to offer him the love and friendship that he so deeply needs.

Startling images underpin the text, the most potent of which is a tree, set on fire by a stroke of lightning, appearing like a burning cross. Beck, who has just survived the terrible storm, strips naked and dries his clothes by it: reborn, he can begin anew. There is a biblical tone to his travails, as if he were making his own pilgrim’s progress; and yet he is no allegory, but a complex, confused adolescent, sometimes brave, sometimes not. He is, in short, human. Vivid, plangent and textured, Beck is a testament to a great talent, which Rosoff has helped to bring into the world both tenderly and passionately.

The trials of the adolescents in Peadar O’Guilin’s striking, eerie The Call are equally brutal, but even more deadly. Hundreds of years ago, the people of Ireland made a treaty with the Sídhe. They agreed that the fair folk would live under mounds, while humans would inhabit the island. But for the last twenty years the Sídhe have been taking their revenge, shrouding the island in mist and stopping new technologies. At any moment from the day they turn ten, an adolescent might hear ‘the Call’ and be pulled into the ‘Grey Land’, where they will be hunted to death by the Sídhe. Few survive, and those who do return with hideous mutations or riddled with psychological problems.

Our heroine, Nessa, struck with polio as a girl, is pitied by everyone. Her twisted legs are useless. She will never be able to outrun the Sídhe; she might as well have died. For this reason, she is determined to succeed. O’Guilin is a powerful writer, ably describing the horrors of the Grey Land (full of Bosch-like creatures), as well as the power plays between teenagers on the point of death. It’s riveting.

The Sídhe are also a force to be reckoned with in the final volume of Catherine Fisher’s Chronoptika Sequence, The Speed of Darkness. Fisher’s writing is taut and unnerving, equally at home with the Italian coastline or the wild hunts of the ‘Shee’. The Chronoptika is an obsidian mirror that is also a portal through time. Those with an interest in it include the Queen of the Shee, a human explorer, a changeling, a scientist and a terrifying tyrant from the end of time whose madness will lead to the destruction of the universe. The plot is in itself a wonder to behold, as multiple strands are effortlessly spun to create a shimmering and uncanny whole. The series is a must for any young (or old) fantasy fan. Its final image, of a host of glittering birds’ eyes in the forest, is one of the most unsettling I have read in a long while.

Not fairies but trolls appear in A F Harrold’s superb The Song from Somewhere Else – or at least, they might be trolls. What is certain is that our world is constantly colliding with others and that sometimes portals appear through which other beings can travel. Sometimes these creatures make the journey unintentionally, as in the case of the troll baby who is accidentally left behind on earth; sometimes they have evil designs, as happens with the frightening insect-like creatures who clamour at the portal, desperate to conquer us. Harrold’s writing is pure and clear, and the development of the friendship between the protagonist, Frank (short for Francesca) Patel, and the loser kid in her class is wonderfully observed. This is a truly magical book, showing awareness of the gulf between child and adult, and of the strangeness of the universe and its many wonders. Like all the best children’s books, it’s about leaving the liminal space of childhood and becoming a whole person. Levi Pinfold’s illustrations are realistic, stark and haunting, like the music of the book’s title.

The power of the imagination is the central theme in Piers Torday’s There May Be a Castle, in which Arthurian legend forms the basis for a different kind of quest. After a car crash, a young boy named Mouse Mallory (see what he did there?) breaks out of the wreck and aims for his grandparents’ house just over the fields. Not so difficult – except that it’s snowing and he’s badly hurt. As he travels, he sees monsters and knights; but are they real or in his head? The narrative is skilfully strung together and the ending deeply surprising, challenging the norms of what might be expected in a children’s novel, which is all to the good.

Another brave and lonely protagonist appears in Lucy Strange’s excellent debut, The Secret of Nightingale Wood, which deploys all the familiar elements of a successful children’s novel in new ways. It’s 1919 and Henrietta’s mother is ill (like all parents in early 20th-century children’s fiction, who are constantly having headaches and needing to lie down), and her father is abroad, leaving the young girl to wander the woods alone, where she encounters someone who may be a witch. She’s also seeing visions of her dead brother and finding more and more secrets in the attic. Strange’s writing is luminous, and she has created a story about friendship, love and family that is wonderfully involving.

A new novel from Jonathan Stroud is always an excitement and The Creeping Shadow doesn’t disappoint. So absorbing was it that I barely surfaced from my room one weekend, following the adventures of the young ghost hunters Lucy and Lockwood as they battle the shades of cannibals in a weird alternative London. ‘The Problem’ – which sees Britain under attack from ghosts – has been going on for years now. Only children can see the visitors, so all the ghost-hunting agencies are staffed by the young. It’s a wonderful conceit and Stroud’s narrative is as thrilling as it is spooky. He has achieved something remarkable, along the lines of Philip Reeve’s Mortal Engines series: a world so detailed and convincing that one longs, despite its terrors, for it to be real. And Lockwood himself – well dressed, handsome, handy with a rapier and hiding a secret – is fabulous.

Finally, The Royal Rabbits of London is the first collaboration between bestselling husband and wife team Simon Sebag Montefiore and Santa Montefiore. The tale follows a young rabbit called Shylo who is sent on a mission to London to prevent some ratzis (the animal-world version of paparazzi) from taking a picture of the queen in her nightie. The premise is very silly, but the book has a sustaining, old-fashioned charm.