Having grown up in a world of manufactured happiness, Lucy, the cynical teenage daughter of a idealistic theme park princess mom, wants to get out and experience something real. When Ian, the new park owner's son, arrives and sweeps her off her feet, Lucy is left wondering if fairy tale endings do exist after all. But when a scandalous secret turns her life upside down, she learns Happyland is far from a walk in the park.
Ripley Holden is a small-time entrepreneur desperate to make it big with his new state-of-the-art amusement arcade. The opening extravaganza is overshadowed by the find of a dead body on the premises. DI Carlisle is called in and quickly finds he has more on his mind than murder, when he falls in love with Ripley's long-suffering wife.
Seiya Kanie, believes that the beautiful but reserved Isuzu Sento has invited him on a date at an amusement park called Amagi Brilliant Park. Much to his chagrin, not only is the location a run-down facility, the supposed date is merely a recruitment tour where Sento and Princess Latifa Fleuranza, the owner of the theme park, ask him to become the park's new manager. Their cause for desperation? As stipulated in a land-use contract, Amagi has less than three months to meet a quota of 500,000 guests, or the park will be closed for good and the land redeveloped by a greedy real-estate company.
Seiya is won over by the revelation that Amagi is no ordinary amusement park; many of its employees are mysterious magical beings who live in the human world and are nourished by the energy created by people having fun. Entrusted with the hopes and dreams of this far-off enchanted land, Seiya must now use his many skills to bring Amagi back on its feet, or watch it crumble before his eyes.