Mycotic aortic aneurysms (MAAs) are a rare form of aortic aneurysms that are associated with catastrophic outcomes if not diagnosed and treated on time. However, MAAs are a diagnostic challenge owing to their often nonspecific presentation. In this study, we present a case of a 42-year-old female with a pertinent history of intravenous drug use who presented with generalized body pain for two weeks and was found to have a mycotic thoracoabdominal aortic aneurysm (TAAA) extensively involving adjacent structures, including lungs with pleural cavity and upper renal pole. Not only does this case highlight the difficulty in early diagnosis and complex pathology of a mycotic TAAA, but it also illustrates the multidisciplinary approach required to effectively treat them.