Alice-Miranda in Japan (Alice-Miranda #9) by Jacqueline Harvey

When Alice-Miranda, Millie and Jacinta travel to Japan during the school holidays, they are in for a fascinating treat. Dolly Oliver, the family cook, has been invited to speak at a conference in Tokyo on her Just Add Water food creation -- but she is even more interested in her newest invention, and vows to try it out while overseas.

Alice-Miranda becomes embroiled in an elaborate missing persons hunt when a gift from her father confuses the authorities. Things come to a head when Alice-Miranda and her friends are invited to dinner at the Imperial Palace in Tokyo, and the plans of a jealous sister begin to unravel, with startling consequences.