The phrase "one at controls" refers to a single person who is in charge or in a position of authority. There are several synonyms for this phrase, including "the person in charge," "the leader," "the manager," "the supervisor," "the boss," "the captain," and "the director". These terms all convey the idea of a person who is responsible for directing and coordinating others. Other phrases that are similar in meaning include "the head honcho," "the chief," and "the top dog." Regardless of the specific term used, the idea of being "one at controls" implies authority, responsibility, and some degree of power.