The Mystery on the Mississippi

It's anchors away for Trixie as she travels down the Mississippi River. No, it's not on the old-fashioned paddle-wheel steamship she always dreamed of, but the trip is still more exciting than she ever imagined. Someone is shadowing her every move, trying to steal to the mysterious graph papers Trixie found in a trash can in her hotel room in Memphis. Why are the papers so important? Could there be more to the childish drawings than meets the eye?