A method and apparatus for exploration of the bile duct is provided wherein an endoscope having a probe of sufficiently small diameter to be inserted into the cystic duct is utilized. The probe has channels therein including conventional illuminating, viewing and irrigation facilities. In addition, a separate passageway is provided for a malleable stylet. This malleable stylet gives the scope the necessary rigidity and shape to be introduced and controlled precisely within the bile duct while at the same time allows the scope to be individually reconfigured as needed during an operation to meet the particular anatomical needs of a patient.