(Portrayed by Majel Barrett-Roddenberry and Rebecca Romijn)
Human female lieutenant and second-in-command under Captain Christopher Pike on the Enterprise NCC-1701. Number One boasted a confident, unflappable manner, even in dangerous situations. In one such instance, she and Yeoman Colt were trapped by the Talosians, who hoped that Captain Pike would take one of them as a mate. She also harbored a secret attraction to the captain.