Two scenarios are presented for chemistry detectives to decipher. Both require the use of an infrared spectrometer and focus on the examination of polymer materials. In the first, lumps in polyethylene bottles are analyzed. In the second, two specific brands of plastic food wrap are compared. Lab groups can choose from one of these two open-ended science inquiries. They are both terrific lessons for studying properties of polymers, spectroscopy, or simply practicing the scientific process.