Ironside

Death by the Numbers (5x20)

Air date: Jan 27, 1972

A string of murders is committed, and in each case the victim has a numbered disk in their possession. After number four is found dead, it transpires that the Commissioner is the owner of disk number six; and the Chief disguises himself as number five - an irascible artist to whom he bears a striking resemblance - in order to keep him alive.