The commander of the powerful alien ship that escorts the comet M'hanit in 2259 and forbids the Enterprise to alter its course, even to save an inhabited planet.
The Shepherd Captain appears in the first-season Strange New Worlds episode Children of the Comet, played by Thom Marriott. His people, whom the crew call the Shepherds, revere the comet M'hanit as an ancient arbiter of life and death and travel with it to keep outsiders away.
When the Enterprise finds that the comet will strike the pre-warp world Persephone III, Pike tries to divert it and sends a landing party to its surface. The Shepherd ship, far stronger than the Enterprise, warns him off, and its captain insists that whatever M'hanit brings is meant to be.
Pike keeps to the letter of the demand while Spock flies a shuttle close enough to heat the ice, so that the comet's own outgassing shifts its path and brings rain to Persephone III. The captain takes the result as proof of his faith.