CASE REPORT: This 30 year women developed severe pain right upper quadrant for last 10 days. She sought many consultations and was given intravenous analgesics both (nonnarcortic and narcotic). Pain did not subside and she sought my consultation. Examination revealed her to be in agony with severe upper abdominal pain. General physical examination was otherwise unremarkable. Abdominal examination revealed mild tenderness in right hypochondrium with doubtful Murphy's sign. Urgent abdominal ultrasound showed a linear structure in bile ducts making slow writhing movements. The structure had an anechoic tube (alimentary canal) inside suggestive of a large Ascarid. Urgent ERCP was performed and bile duct and pancreatic duct cannulated selectively. Pancreatic duct was normal. Bile ducts contained a long linear filling defect extending from lower end of common bile duct to right intrahepatic duct (see image gallery for ERCP plate). A basket was introduced in the duct (see video clip) and the linear structure was engaged with soft closure and extracted out of the bile duct. Accompanying the basket was a 25 cm thick highly motile Ascarid. To recover the worm, endoscope was withdrawn along with the basket and the friendly catch. While the endoscope was being withdrawn and the basket was in the duodenum with the worm out of bile duct, patient indicated of relief of abdominal pain. A relook cholangiogram showed no more structures in the duct. She was given antihelmintic therapy and passed hundreds of worms with the feces. The worms recovered form stools were both male and female population and varied in length and size. However the lone worm recovered form bile ducts was the longest and the thickest male worm. The phenomenal behavior of this ubiquitous infection remains unexplained.