Argon plasma coagulation is increasingly used in endoscopic haemostasis. This case report illustrates the potential for thermal injury at a staple line remote from the area of argon plasma coagulation treatment as a result of electrical arcing. Increasing numbers of colorectal anastomosis and reconstruction procedures are now being performed using stapling techniques and the use of argon plasma coagulation in these patients has become a common situation in clinical practice. Information about this potential danger should be well disseminated to endoscopists and surgeons to avoid preventable complications. The presence of a staple line nearby should be considered a contra-indication for argon plasma coagulation.