Hirai

Doctor Hirai was a Human Starfleet officer, and one of the Federation's leading specialists in astrolinguistics, xenophonology, and theoretical semiotics in the late 32nd century.

Dr. Hirai had worked closely with Dr. Kovich, who introduced Hirai to ancient Earth crossword puzzles.

In 3190, he served on the DMA task force to offer his expertise in establishing parameters for successful communication with Unknown Species 10-C. Though Dr. Kovich could not join the mission to make first contact, he trusted Dr. Hirai's expertise to offer direction in communications to the USS Discovery and the accompanying delegates in crossing the galactic barrier. (DIS: "The Galactic Barrier")

He was later in the shuttlebay to see the away team off to what appeared to be the Species 10-C homeworld, where his bluntness in speaking to Captain Michael Burnham added to the stress and panic some of the delegates were feeling. Federation President Laira Rillak later spoke with him in Discovery's lounge while he was working on a crossword puzzle, where she asked him to exercise more tact during the mission. (DIS: "Rosetta")

Dr. Hirai continued to offer guidance and advice through attempts to communicate with Species 10-C, managing the task force's expectations around how the 10-C may interpret or be unable to interpret their efforts. Eventually, he worked with Zora to construct math-based messages the 10-C could understand. When the 10-C sent an orb to further facilitate communication, President Rillak volunteered to enter the orb, instructing Dr. Hirai to stay behind to resume diplomacy if something were to happen to them (to his disappointment.) (DIS: "Species Ten-C")

In the final hours before the DMA debris was set to hit Earth, Dr. Hirai continued efforts to ask the 10-C to release Discovery from an orb they had been held in. He suggested to the task force that the 10-C likely presumed Discovery, Cleveland Booker and Ruon Tarka were working together, and continued managing and interpreting communication efforts, along with Saru, with the 10-C, until the crew were able to convince the 10-C to stop the DMA. (DIS: "Coming Home")