A Short History Of Number One In The Star Trek Universe

If you're exploring the cosmos and going where no one has gone before, it makes sense to have someone reliable at your side. In "Star Trek: Strange New Worlds," Captain Christopher Pike commands the classic Enterprise with Lieutenant Spock as his third. His second-in-command is the steadfast Number One.

But "Number One" is just a nickname. The character's real name is Commander Una Chin-Riley, with Rebecca Romjin reprising the role after her appearances in "Star Trek: Discovery." Like Pike himself and the ship's medical officer, Doctor M'Benga, "Strange New Worlds" has the chance to finally add some more color and life to characters that had only brief appearances in the original "Star Trek".

Number One first appeared in the original pilot episode of "Star Trek." Entitled "The Cage," the pilot introduces us to the crew of the starship Enterprise, though it's a slightly different iteration from the one most people know. At the helm of this ship is Captain Christopher Pike and his first officer a woman simply known as Number One.

The character was played by actress Majel Barrett, who would transition over to the original series as a different character, Nurse Christine Chapel. In the pilot episode, Number One is a stoic figure, betraying very little emotion and focusing entirely on the business at hand. When Pike is kidnapped on a mission to Talos IV, Number One elects to be a part of the landing party that goes to find him.

Things don't go as planned and Number One becomes kidnapped by the Talosians as well, with the aim of providing Pike with a selection of potential mates. The leader of the Talosians, the Keeper, even notes that Number One's professional demeanor is a shield over her feelings for Pike. Ultimately, Number One sets her weapon to overload in an attempt to stop the Talosians' plans.

Number One was never seen again in the original continuity, as Barrett was now playing Nurse Chapel. There's no indication whether she had a further career with Starfleet after the mission shown in "The Cage." Barrett would later marry series creator Gene Roddenberry, becoming Majel Barrett Roddenberry, and appear as Lwaxana Troi in "Star Trek: The Next Generation."

Number One returned later in "Star Trek: Discovery" and the adjoining "Short Treks" mini-series. In the "Short Treks" episode "Q&A," the newly-assigned Ensign Spock finds himself trapped in a turbolift with the Enterprise's first officer, giving him a chance to ask her about the Captain and the rest of the ship. It's a light episode, mostly played for laughs.

Writer Michael Chabon told Syfy Wire that he also used the episode to explain the differences between the more emotive Spock in the pilot and his later characterization in "Star Trek." The answer? He took after the first officer he met on his first day on the Enterprise — the impassive Number One.

Number One guest-starred on "Discovery" when Pike took over as Captain for the Discovery in season 2. In the episode "An Obol for Charon," the Enterprise itself is disabled and in spacedock, giving Number One and Pike the chance to discuss murder allegations against Spock. Number One comes across as fiercely protective of Spock, even noting that she did some sanctioned digging to find information about the case.

Number One appears again in the season finale for the second season of "Discovery," welcoming Pike and Spock back to the ship.

In "Strange New Worlds," Number One is finally given her full name: Una Chin-Riley. And as we see in the new Paramount+ show, Commander Una is a first officer who is more than willing to take charge of a situation. She's sadly missing for most of the first episode however, as her capture during First Contact is what gets Pike back onboard the Enterprise.

Still, the series now has a chance to define Number One far beyond her brief appearance in the pilot episode. And Rebeccca Romjin gets the chance to show why Pike calls her "the best first officer in the fleet."