The LaFontanne Chemical Company is shipping out a load of we're not sure what, disguised as something entirely different. Mr. Pereaux and Mr. Grock don't want that shipment to ever arrive anywhere, and they and a man named Aquirre mean to stop it at any cost. The ship's owner, Mr. Fontanne, smells a large rat and calls Chan in on the case, since the famous detective is in New Orleans because, well, because he felt like being in New Orleans, I guess. Chan gets what facts there are from LaFontanne, who is promply set upon by a gang who attempt to kidnap him, but fail. Mr. LaFontanne's partners come up with some insurance; just by chance they tell him, a partnership agreement (why they would have been running a company all this time without one is another large mystery which will not be solved) that bestows upon the living partners the portion owned by a deceased partner.