The box set contains 4 books from the series: Cogheart: Lily’s life is in mortal peril. Her father is missing and now silver-eyed men stalk her through the shadows. What could they want from her? With her friends – Robert, the clockmaker’s son, and malkin, her Mechanical Fox – Lily is plunged into a murky and menacing world. Too soon Lily realises that those she holds dear may be the very ones to break her heart... Murder, mayhem and mystery meet in this gripping Victorian adventure.Moonlocket: storm clouds gather over Lily and Robert’s summer when criminal mastermind the Jack of diamonds appears. For Jack is searching for the mysterious. Moonlocket – but that’s not the only thing he wants.Soon, dark secrets from Robert’s past plunge him into danger, because Jack is playing a cruel game. Lily and malkin, the Mechanical Fox, must stay one step ahead before Jack plays his final, deadly, card... Skycircus: treachery, tight-ropes and trickery combine in this incredible third Cogheart adventure…when a travelling circus arrives in brackenbridge, Lily and Robert can’t wait to step aboard… but there’s something sinister about the hybrid children who appear as part of the Act. And before Lily and Robert can do anything, they've captured by shadowy figures and whisked off in the mysterious flying circus to somewhere far, far away… shadowsea: swept into the bright hustle and bustle of new York, Lily, Robert and malkin discover shadowy secrets lie beneath its surface. For there are chilling goings-on in their hotel… a strange boy held captive, haunted by an undersea mystery; and a revengeful villain with a treacherous plan.Searching for clues, Robert and Lily are plunged into deep water… but can they reveal the deadly truth before the secrets submerge them? Join Lily, Robert and malkin on a fantastic voyage of terror and triumph, in the thrilling fourth and final Cogheart adventure….