You must file an Ex Parte motion in your current case that asks for emergency custody. Emergency custody is only granted under certain conditions, so you will need to allege sufficient conditions under NC General Statutes 50B-2 and 50-13.1 and 50B-3. You should also write an affidavit (simply a statement on paper) and have it notarized and attached to your motion. The affidavit should contain your reasons for wanting emergency custody.
Depending on what county you reside, there may be a an Ex Parte or Emergency Custody form located with the Clerk's office.