 Mrs. Brown s bad violin playing is causing Martin to short circuit and become transparent. Actually, it s the bad violin itself causing the problems. They know they can t convince Mrs. Brown to stop playing, so Martin breaks it so that he can fix the fundamental structure of the violin. He finds that the violin is not as bad as it first seems, it just has a few fundamental flaws. The violin maker is Mrs. Brown s teacher, Signor Almafi, his family violin business in threat of going under due to the poor quality of the instruments. After hearing the new and improved instrument, Amalfi believes he did something right to make such a beautifully sounding instrument, but what? So all Martin has to do is pass on the information to Amalfi without him knowing the real source.