We present an inadvertent unusual complication of a double square knot found within a PICC in this case report. PICCs are known to cause catheter-related bloodstream infection, catheter malfunction, thromboembolism, catheter migration, and catheter fracture is reported. But the occurrence of double square knot is the rarest complication during insertion which led to unexpected challenges during removal and to our knowledge there are no case reports of this rarest event. We discuss the case presentation, management, and clinical implications of this rare complication.