It was a small note-written in German. Pete Hollister found it hidden in the door of a broken cuckoo clock. When the note was translated, the Hollister children were jubilant. The message was a riddle that made little sense to them-but it was the first clue in a brand-new mystery. Imagine their surprise when Mr. Hollister announced that the whole family-Pete, Pam, Holly, Ricky, and little Sue-were going to Germany to buy toys for their shop,...