This paper deals with the different aspects of the human physiology related to the cardiovascular system, nervous system, kidneys and endocrine system with respect to the hot tub death case study. In this case, a couple has been found dead in their hot tub, without any apparent injury or reason of death. From the data available in the scene and in the couple’s house, it can be concluded that the man, Mr. Underhill, had heart problems and used Lasix to keep his blood pressure and hyper tension in control. Also, the couple was quite drunk and their Blood Alcohol Level was quite high at 0.2. The coroner’s report mentioned that Mr. Underhill had traces of lasix. Mrs. Underhill did not have any lasix content. The tub water was very hot at 48.1 degrees. The paramedics and other professionals involved in the case could not point out the reason of death clearly but concluded that the wine, lasix and the hot water, all could have influenced the deaths in some way. The investigator dealing with this case, Detective Garrison, realized that a lot of physiological issues were involved in this case. Hence, he seeks guidance from a physiologist in the Healthcare department. The physiologist explained the causes of death clearly and has used this case for a lecture to post registration nursing students undertaking an applied physiology class. The exact reason of death could not be understood from the evidence gathered at the scene of death. The aim of this paper is to consider and analyze the different factors that might have caused the deaths in this scenario.