Before they officially become United States Marines, all recruits must endure "The Crucible," an event that tests them physically and psychologically for 54 straight hours with minimal sleep and food. Chief video correspondent Graham Flanagan spent four days at the Marine Corps Recruit Depot in Parris Island, South Carolina, embedded with the gender-integrated Hotel Company during its Crucible event. Among the recruits were a brother and sister both experiencing the event together. Recruits hike for miles in the cold darkness wearing about 50 pounds of gear, face off in hand-to-hand combat inside the "Octagon," experience intense combat scenarios and work together to overcome obstacles that test their bodies and minds. The event culminates with the emotional Eagle, Globe, and Anchor Ceremony, where the recruits receive a pendant that symbolizes their official transformation into United States Marines.