Things we lose at home are taken by 'Borrowers', tiny folk who live with us, discovers 'human bean' Rosita Boland, as the show of the children's book, The Borrowers, opens in Cork

We are human beans. The Clock family are Borrowers. They're what? Borrowers, or tiny people, less than six inches high, who secrete themselves away and survive on what they can "borrow" from us, the human beans.

Next year is the centenary of the birth of children's author Mary Norton and this year marks the 50th anniversary of the publication of the first book about the Clock family: The Borrowers.

There are five books in the series, based on a simple but wonderfully ingenious idea. Who has not mislaid small items within their house and never found them again? In Norton's books, those items - pins, spools, chess-pieces, scraps of material, cigar boxes, thread and countless others bits and pieces - end up furnishing Borrowers' makeshift homes. They are makeshift because they are usually temporary. Once a Borrower has been "seen" by a human, he or she must move on at once, since attempted capture, even if prompted by well-meaning curiosity, always follows.

The Borrowers books are classics; beautifully written, imaginative, and populated with memorable characters. Pod, the father, is brave, philosophical, and resourceful; Homily, the mother, is a worrier who longs for stability; and their daughter, spirited Arrietty, dreams of freedom and the outdoors, and she alone welcomes the adventures which result from enforced move to the fields outside when they are seen by the small boy of the big house in which they live.

Borrowing, for the uninitiated, bears no relation to that anti-social activity, stealing. The Borrowers only borrow things which are lying around, items which won't be noticed (usually) when removed, and which are useful to their needs. A potato will last for weeks, little pieces cut off with a piece of blade from a nail-scissors. Arrietty's bedroom is made of an old cigar box. Homily hangs her washing from a rack composed of safety pins, while longing for the grand furniture from the doll's house, which Pod can never borrow, since its absence would be noticed.

In each of the books, the narrative is focused on a hunt for the family, with all its scarily convincing consequences explored in Norton's gripping storytelling. If you are only a few inches high, the world is full of potential dangers. A field is as big as a county and humans are giants. And it's not only humans they fear. Creatures such as cats and rats are like unimaginably huge wild animals. Only by ingenuity and courage can they survive and escape their captors: making a boat from a cutlery box, a home from an abandoned kettle, and most memorably of all, in The Borrowers Aloft, soaring out the window of their attic prison with an ordinary balloon tied to a home-made basket.

A British  company, Watershed Productions, has adapted the first book, and it is opening tonight at the Cork Opera House. It's an appropriate venue for the show, since Mary Norton lived in Leap, Co Cork, for 20 years.

However, it's a brave move to attempt to transfer this unique miniature world to a stage, when the world of the Borrowers can, arguably, only exist in the pages of Norton's prose and in the reader's imagination.

Whether audiences love or hate Watershed's production, it's certain that, afterwards, some children will search out Norton's books, and that their parents will read them with as much pleasure as they did when they were young.

• The Borrowers is at Cork Opera House until Saturday. Booking: 021-4543210