Introduction We describe a case of an intracrural collection as a complication of an oesophageal perforation due to a fish bone. Case Presentation A 56-year-old male presented with a 5-day history of chest pain associated with fever, following the ingestion of a fish bone. His CT imaging showed a 1 x 10 x 1cm left subdiaphragmatic collection adjacent to the gastro-oesophageal junction (GOJ) and cardia of stomach, suggestive of a contained perforation. The patient was initially managed conservatively, but deteriorated clinically during his admission. A repeat CT showed an increase in size of the collection, complicated by a large left-sided pleural effusion with complete collapse of the left lower lobe. The patient underwent an emergency laparoscopic drainage of the collection. Intra-operatively, the diaphragm was acutely inflamed, and the collection was found to be within the left crus requiring dissection to ensure adequate drainage. This was followed by an endoscopy which revealed a sealed pinhole defect near the GOJ, likely to be the site of perforation. Discussion This case highlights that clinical presentation of oesophageal perforation can be variable and often delayed, requiring a tailored management utilising various approaches. While non-operative approach can be considered in selective cases like ours, there should be a low threshold to intervene depending on the clinical situation. References 1. Gheorghiu MI, Bolliet M, David P, et. al. Case report of abdominal left upper quadrant collection secondary to fish bone perforation. Med Pharm Rep. 2020;93:301-5 2. Yamamoto M, Yamamoto K, Sasaki T, et. al. Successfully treated intra-abdominal abscess caused by fish bone with perforation of ascending colon: a case report. Int Surg. 2015;100:428-30