Ferroptosis is a form of programmed cell death associated with iron-dependent lipid peroxidation. Novel ferroptosis inducers and suppressors could be instrumental in developing drugs against neurodegenerative disorders and cancer. Prior to embarking on a search for ferroptosis inducers/suppressors, this form of cell death must be studied in living cells and laboratory animals. In addition to two cofactors, luciferase (or photoprotein) of the parchment tubeworm Chaetopterus variopedatus requires the presence of iron ions and hydrogen peroxide or organic hydroperoxides to exert its activity. Therefore, the bioluminescence system of the parchment tubeworm can be used to study ferroptosis in living organisms.