N.C. Gen. Stat. § 1-166: Defendant sued in fictitious name; amendment.

When the plaintiff is ignorant of the name of a defendant the latter may be designated in a pleading or proceeding by any name; and when his true name is discovered, the pleading or proceeding may be amended accordingly. (C.C.P., s. 134; Code, s. 275; Rev., s. 510; C.S., s. 550.)