This Enchanted Island — Tansy Rayner Roberts

Miss Metis Seabourne flees scandal and humiliation in the Teacup Isles for a Continental sea voyage… and quite happily gets herself kidnapped by privateers.On board the Caliban, Metis finds a new family of misfit, piratical rogues including the handsome Captain Bones and his dazzling first mate, Calypso. She ditches the teagowns for britches, and learns to feel capable rather than ladylike. For the first time in her life, she is free to be herself.But her old world, of house parties and croquet, returns with a jolt after the crew of the Caliban get tangled in a caper with a runaway queen and the mysterious Isle of Dream with its mermaids, sea witches and whimsical wild magic. Caught between two people she loves, and determined not to return to being the social failure of the Seabournes, Metis must learn to be braver than she’s ever been before.