 Unable to persuade the aliens to release him, Frisby decides to try to relax by playing his harmonica, and makes the unexpected discovery that the sound is extremely painful to the aliens (who call the notes "death sounds").After two or three aliens are rendered senseless by the harmonica, the remaining ones permit Frisby to escape.Running back to the general store, he finds his friends waiting to throw him a surprise party (in the evening's excitement, he had forgotten that it is his birthday).