A 42 year old man presented approximately 10 days after a motorbike accident with fever, right upper quadrant pain and systemic sepsis. Initial CT imaging demonstrated a large gas containing right hepatic subcapsular collection associated with segment VI/VII injury, favoured to represent an infected post traumatic haematoma or evolving liver abscess. There was no convincing early evidence of diaphragmatic disruption or intrathoracic involvement. Initial management focused on antimicrobial therapy and abdominal source control.During admission the patient deteriorated with recurrent hypoxia, hypotension and escalating inflammatory markers, prompting multiple MET calls and transfer to intensive care. The severity of respiratory compromise was unexpected and disproportionate to abdominal findings. Progressive unilateral pulmonary consolidation developed. Bronchoscopy at intubation revealed a large volume of purulent material within the right bronchial tree. Repeat CT imaging demonstrated a defect in the right hemidiaphragm with direct communication between the hepatic collection and the right lung parenchyma, consistent with transdiaphragmatic fistulation.Despite interventional drainage and broad spectrum antimicrobials, the patient developed necrotising pulmonary infection with persistent air leak and respiratory failure. Management required coordinated multidisciplinary intervention. Operative treatment included laparotomy with drainage of a subphrenic abscess and diaphragmatic repair, followed by right thoracotomy and bilobectomy for non viable lung. Cultures grew Streptococcus milleri.This case illustrates how post traumatic hepatic sepsis may extend beyond the abdomen with minimal early warning. Clinical deterioration discordant with initial imaging should prompt early reassessment, repeat imaging and timely multidisciplinary source control.