Jackie lives in Dublin where the horses run free near the tower blocks. She longs for a horse, but must be content with her donkey, who is as stubborn as a mule. Her dream - that he will run like a racehorse - is granted by Mister Skip, a gnome she has rescued from an old skip.

Set in Dublin where horses run wild in the fields near the tower blocks, Jackie watches the boys on the estate ride their horses and she longs to own her own horse. All Jackie has is her Gran's old donkey Barnaby, who is a stubborn as...a mule! One day, whilst rummaging in an old skip, Jackie finds a broken garden gnome whom she restores back to his former glory and gives to her Mum for her birthday. Much to her astonishment, Mr Skip talks to Jackie! Because she gave him a new lease of life, he is going to help make her dreams come true. Her wish is, of course, for her donkey to 'run like a racehorse'. Jackie challenges the boys to a race and, at first, Barnaby just refused to move. Then, she whispers the magic words into his ear - 'Do it for Mister Skip' and Barnaby tears away and wins the race. Fame and...almost fortune...come Jackie's way, with TV appearances, a film-deal and a promised million 'smackaroos'. But can Barnaby, the Superdonk, win the Irish Derby? Can Mister Skip work his magic till the very end?