We present a case of a previously well 24-year-old female patient who developed severe and life-threatening Irukandji syndrome that required ventilation and inotropic support. This case provides further evidence that there are jellyfish other than the Irukandji jellyfish that can cause cardiac decompensation, and there is a suggestion that application of a pressure immobilization bandage may worsen the envenomation. We include our recommended treatment for the Irukandji syndrome.