Don Margello is a mob boss whose life was saved by Frank Castle after two of Francesco Drago's assassins tried to kill him. At the time, Castle was working as a dishwasher at a restaurant and noticed two criminals barging into the restaurant and stopped them. After that, Margello noticed how skilled Castle was and wanted to recruit him as a hitman to kill Francesco Drago. Castle only accepts Margello's offer when he notices Margello's men are patrolling his home. However, Castle really just planned on killing Margello and his men instead of Drago, but Nick Fury intervened and had his agents kill Margello and his men to keep Frank Castle's family safe.