Fresh off the announcement that Anson Mount will be captaining the Enterprise as Christopher Pike, news is breaking today that CBS has cast actor Rebecca Romijn to be his first officer, previously known only as ‘Number One’ in “The Cage.”

Perhaps best known to genre fans as the adult Mystique in the X-Men films, Romijn has recently starred in TNT’s The Librarians, along with several other high-profile roles in her career.

The actor tweeted shortly after the announcement, with gold Starfleet uniform visible in her photo:

Just call me “Number One!” Honored to play such an iconic character in #StarTrek Canon originally played by the First Lady of Star Trek, Majel Barrett-Roddeberry! #StarTrekDiscovery pic.twitter.com/rdpWOxBYAk — Rebecca Romijn (@RebeccaRomijn) July 20, 2018

Originally played by Majel Barrett in the original Star Trek pilot — and later seen in archival footage during “The Menagerie” — the character of ‘Number One’ was eliminated from the series after NBC executives, as well as test audiences, responded negatively to the female officer.

Here’s Gene Roddenberry’s original description of the character, from the original Star Trek is… pitch document when he first developed the series (back when Captain Robert April was still the lead character).

The Executive Officer: Never referred to as anything but “Number One”, this officer is female. Almost mysteriously female, in fact – slim and dark in a Nile Valley way, age uncertain, one of those women who will always look the same between years twenty and fifty. An extraordinarily efficient officer, “Number One” enjoys playing it expressionless, cool – is probably Robert April’s superior in detailed knowledge of the equipment, departments, and personnel aboard the vessel. When Captain April leaves the craft, “Number One” moves up to Acting Captain.

While the character never reappeared in Star Trek after “The Cage,” she has made a number of appearances in both comics and novels, given different ‘real’ names by many authors over the decades.

Most recently, when she’s appeared in Simon & Schuster tie-in novels such as 2016’s Star Trek: The Original Series – Legacies trilogy, and David Mack’s Discovery novel Desperate Hours, she’s been named Lt. Commander Una.

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