Cosmo's brother Brian died when he was ten years old. His mum hides her grief by working all the hours God sends & Cosmo lives with his grandparents. They've been carefree days as Granddad buys him a horse called John & teaches him all he knows about horses. But the good times have to come to an end & although he doesn't want to admit it Cosmo knows his Granddad is losing his mind. So on one of the rare occasions when Granddad seems to recognise him Cosmo is bemused that he gives him a key to Blackbrick Abbey & urges him to go there. Cosmo shrugs it off but gradually Blackbrick draws him in... Cosmo arrives there scared & lonely & is dropped off at the crumbling gates of a huge house. As he goes in the gates close & when he turns to look they're rusty & padlocked as if they haven't been opened in years. Cosmo finds himself face to face with his grandfather as a young man & questions begin to form in his mind: can Cosmo change the course of his family's future?