A 34-year-old woman is admitted to the hospital with dyspnoea, dry cough and left-sided flank pain. Her Legionella urinary test was positive and CT imaging demonstrated multifocal pneumonia with pulmonary abscesses. Although she had initial clinical improvement on appropriate antibiotic therapy, her hospital course was complicated by worsening flank pain, hypoxemia and leucocytosis, prompting clinical re-evaluation and assessment for development of complications involving the pleural space. CT imaging revealed interval development of a loculated complicated parapneumonic effusion. Successful treatment required chest tube drainage assisted by fibrinolytic therapy. This case highlights the importance of considering Legionella in patients with pulmonary abscess, demonstrates an approach to a patient with a non-resolving pneumonia and illustrates the management of parapneumonic effusions.