Riki, a 10-year-old boy, runs away from home following a mysterious emergency signal sent by a shiny stone. The strange artefact leads Riki to a breathtaking parallel world called Yourland, where wonderful machines roam golden deserts, monkeys and ravens talk, and science peacefully coexists with nature. The shining stone merges with Riki by hiding in his heart and asking him for protection. It seems everybody in Yourland is eager to procure this treasure, as it is the core of Yourland’s power and owning it provides a great deal of influence. Riki embarks on an enchanting journey full of perils, traps and humour to restore the stone, the “Heart of a Tower”, to its nesting place. It is the only way for Riki to get back home and save his own heart.