Number One Becoming A Replacement Changes Star Trek’s Doppelganger Rules

Image credit: Paramount+ Published Aug 17, 2026, 8:00 AM EDT John Orquiola is a New & Classic TV Editor, Senior Writer, and Interviewer with a special focus on Star Trek. John has over 5,000 published articles at SR, and he has interviewed the biggest names in Star Trek on the red carpet and VIP events, among other beloved shows, movies, and franchises. Sign in to your ScreenRant account Warning: SPOILERS for Star Trek: Strange New Worlds Season 4, Episode 4 - "A Case of Chiaroscuro"Commander Una Chin-Riley (Rebecca Romijn) replacing her exact double in Star Trek: Strange New Worlds changes what we know about Star Trek doppelgängers. Directed by Meera Menon and written by Skylar Ojeda and Dana Horgan, Star Trek: Strange New Worlds season 4, episode 4, is a film noir homage to Casablanca that centers on Number One. In Star Trek: Strange New Worlds season 4, episode 4, "A Case of Chiaroscuro," Una, Dr. Joseph M'Benga (Babs Olusanmokun), and Ensign Nyota Uhura (Celia Rose Gooding) are stranded on Mat'Aar XII, a planet under Klingon occupation. The Starfleet officers must go undercover on Mat'Aar, a planet whose sun emits radiation that renders everything in black and white. Number One is immediately mistaken for Nevette, a Klingon collaborator who works directly with Mat'Aar's Klingon governor, Commander Kor (Demore Barnes). However, Nevette is also secretly the leader of Mat'Aar's resistance. Una and Nevette are so identical that only Roman (Andy McQueen), who murdered the real Nevette, knew that the USS Enterprise's First Officer was an impostor. Star Trek: Strange New Worlds Reveals Characters Have Unexplained Doppelgangers Image credit: Paramount+ How Una Chin-Riley and Nevette can be identical goes unexplained in Star Trek: Strange New Worlds season 4, episode 4. The bizarre coincidence is hand-waved away by Dr. M'Benga, who suggests to Uhura that in such a vast universe, he finds it surprising that they don't run into their doubles more often. That's all well and good, but it's a very thin rationale for Star Trek. "A Case of Chiaroscuro" is a film noir and plays by those established tropes. Characters having identical doppelgängers is a staple of film noir, and even classic literary works. "A Tale of Two Cities" by Charles Dickens, which was lovingly referenced in Star Trek II: The Wrath of Khan, hinged on Charles Darnay and Sydney Carlton being identical. Yet scientific (or even pseudo-scientific) rationales are expected of Star Trek, and "A Case of Chiaroscuro" sidesteps how Una and Nevette can be exactly the same. Somehow, Number One looks and even sounds exactly like Nevette and is able to easily replace the Mat'Aar resistance leader. No one besides Nevette's killer can tell any difference, not even Commander Kor. The contrivances that "A Case of Chiaroscuro" requires audiences to accept include everyone on Mat'Aar XII speaking English (or whatever standard language is used in Star Trek), and Una and Nevette not only looking the same but also sounding exactly alike. Thus, on this black and white world located in Klingon space, Nevette is a perfect lookalike of genetically engineered Illyrian Una Chin-Riley in every way, and Number One just happened to land on Nevette's planet and was able to impersonate her without fail. Why Strange New Worlds Just Rewrote Star Trek’s Rules Of Exact Doubles Star Trek characters meeting their doppelgängers is nothing new, and has been happening since Star Trek began 60 years ago. There is usually an explanation, and the most common is a transporter malfunction, starting with Captain James T. Kirk (William Shatner) being split into his good and evil sides in Star Trek: The Original Series season 1's "The Enemy Within." Stardate 47988.1 · Crew Assessment The Final FrontierTrivia Challenge 🚀ShipsEnterprise! ⭐CrewMake it so ☠EnemiesResistance is… ⚡TechWarp speed! 📖LoreLive long… ENGAGE → 01 The USS Enterprise is the most iconic starship in science fiction. What is the registry number of Captain Kirk’s original Enterprise from The Original Series? ANCC-1701-D BNX-01 CNCC-1701 DNCC-74656 ✓ Correct! NCC-1701 is the registry of Kirk’s original Constitution-class Enterprise. The “-D” suffix belongs to Picard’s Galaxy-class ship, NX-01 is Archer’s Enterprise, and NCC-74656 is Voyager. ✗ Red alert! The answer is NCC-1701. Kirk’s original Constitution-class Enterprise carried this now-legendary registry. NCC-1701-D is Picard’s Enterprise from TNG, NX-01 is Captain Archer’s, and NCC-74656 belongs to Voyager. NEXT → 02 Kirk’s most trusted officer is a half-human, half-Vulcan science officer famous for his logic and iconic salute. Who is this legendary character? AData BSpock CTuvok DSarek ✓ Correct! Mr. Spock, played by Leonard Nimoy, is the half-Vulcan science officer whose “Live long and prosper” salute became a cultural icon. His struggle between logic and emotion defines the heart of the Original Series. ✗ Red alert! The answer is Spock. Data is an android from TNG, Tuvok is Voyager’s Vulcan tactical officer, and Sarek is Spock’s Vulcan father. Only Spock is the half-human, half-Vulcan first officer of Kirk’s Enterprise. NEXT → 03 Starfleet’s most important regulation forbids interference with the natural development of alien civilizations. What is this guiding principle called? AThe Temporal Accord BGeneral Order One CThe Omega Directive DThe Prime Directive ✓ Correct! The Prime Directive (also known as General Order 1) is Starfleet’s most sacred law. It prohibits interfering with less-developed civilizations — though Kirk, Picard, and Janeway have all famously bent or broken it when lives were at stake. ✗ Red alert! The answer is the Prime Directive. While “General Order One” is technically another name for it, the Prime Directive is the universally known term. The Omega Directive and Temporal Accord are separate, more specialized Starfleet protocols. NEXT → 04 “Resistance is futile.” This chilling declaration belongs to a cybernetic collective that assimilates entire civilizations into its hive mind. What is this fearsome species called? AThe Borg BThe Dominion CThe Romulans DSpecies 8472 ✓ Correct! The Borg are Star Trek’s most terrifying villains — a hive-mind collective that forcibly assimilates species and technology. Captain Picard was famously assimilated and transformed into Locutus in the landmark TNG episode “The Best of Both Worlds.” ✗ Red alert! The answer is the Borg. The Dominion is the Gamma Quadrant empire from DS9, the Romulans are a rival empire, and Species 8472 is actually one of the few species that the Borg themselves fear. Only the Borg declare “Resistance is futile.” NEXT → 05 Captain Jean-Luc Picard commands the Enterprise-D in The Next Generation and later received his own series, Star Trek: Picard. Which acclaimed actor portrays him? AWilliam Shatner BAvery Brooks CPatrick Stewart DScott Bakula ✓ Correct! Sir Patrick Stewart brought gravitas, Shakespeare, and Earl Grey tea to the captain’s chair for seven seasons of TNG, four films, and three seasons of Star Trek: Picard. His “Make it so” is one of TV’s most iconic catchphrases. ✗ Red alert! The answer is Patrick Stewart. William Shatner plays Captain Kirk, Avery Brooks is Captain Sisko on Deep Space Nine, and Scott Bakula captains the NX-01 Enterprise. Only Sir Patrick Stewart portrays the legendary Jean-Luc Picard. NEXT → 06 Starfleet vessels travel faster than light by bending space around them using a matter-antimatter reaction. What is this propulsion system called? ATranswarp Drive BWarp Drive CSlipstream Drive DSpore Drive ✓ Correct! Warp Drive is the standard faster-than-light propulsion in Star Trek, powered by dilithium-regulated matter-antimatter reactions. Zefram Cochrane invented it in 2063, which led to humanity’s first contact with the Vulcans. ✗ Red alert! The answer is Warp Drive. Transwarp is an advanced Borg technology, Slipstream is an experimental quantum drive, and the Spore Drive uses mycelial network navigation (from Discovery). Standard Starfleet vessels use Warp Drive. NEXT → 07 At Starfleet Academy, cadets face a notorious no-win scenario designed to test their character under impossible circumstances. James Kirk is the only cadet who ever beat it — by cheating. What is this test called? AThe Prometheus Trial BThe Omega Simulation CThe Corbomite Maneuver DThe Kobayashi Maru ✓ Correct! The Kobayashi Maru is an unwinnable rescue simulation that tests how cadets handle certain death. Kirk reprogrammed it so he could win — earning a commendation for original thinking. It was memorably featured in Star Trek II: The Wrath of Khan. ✗ Red alert! The answer is the Kobayashi Maru. The Corbomite Maneuver is a TOS episode, not an Academy test. The Kobayashi Maru is the famous no-win scenario that Kirk defeated by reprogramming the simulation — because he doesn’t believe in the no-win scenario. NEXT → 08 In the widely regarded greatest Star Trek film, a genetically enhanced superhuman from Earth’s past seeks revenge against Captain Kirk. “KHAAAAN!” Who is this iconic villain? AKhan Noonien Singh BGeneral Chang CQ DGul Dukat ✓ Correct! Khan Noonien Singh, played by Ricardo Montalbán, is Star Trek’s greatest villain. First appearing in the TOS episode “Space Seed,” he returned in The Wrath of Khan (1982) for a devastating revenge plot that cost Spock his life. ✗ Red alert! The answer is Khan Noonien Singh. General Chang is a Klingon from Star Trek VI, Q is TNG’s omnipotent trickster, and Gul Dukat is DS9’s Cardassian antagonist. Only Khan inspired Kirk’s legendary scream across the cosmos. REVEAL MY SCORE → Mission Complete Your Starfleet Record / 8 Are you an Admiral — or still a cadet on deck-scrubbing duty? ↻ RE-ENGAGE A transporter accident created Commander William Riker's (Jonathan Frakes) exact double, Thomas Riker, in Star Trek: The Next Generation season 6's "Second Chances." Star Trek: Lower Decks comically repeated TNG's transporter duplication, creating Ensign Bradward Boimler's (Jack Quaid) transporter clone, William Riker. The Romulans cloned Captain Jean-Luc Picard (Patrick Stewart) with Shinzon (Tom Hardy) in Star Trek: Nemesis. However, the easiest way for Star Trek to introduce doppelgängers is via the Multiverse. From the evil versions of Star Trek characters in the Mirror Universe, to the many other alternate timelines that exist, virtually everyone in Star Trek has a duplicate somewhere out there. Ultimately, Star Trek: Strange New Worlds' "A Case of Chiaroscuro" didn't find it important to conjure an explanation for how Una and Nevette were identical. Instead, the episode's technobabble rationale centered on why everything was black and white. However, this also means that characters' exact doubles randomly existing is a thing now in Star Trek canon. Star Trek: Strange New Worlds season 4's new episodes premiere Thursdays on Paramount+ Release Date 2022 - 2027-00-00 Network Paramount+ Showrunner Henry Alonso Myers, Akiva Goldsman Directors Dan Liu, Amanda Row, Maja Vrvilo, Akiva Goldsman, Dermott Downs, Eduardo Sánchez, Jeffrey W. Byrd, Jonathan Frakes, Jordan Canning, Leslie Hope, Valerie Weiss, Sydney Freeland, Christopher J. Byrne, Rachel Leiterman Writers Onitra Johnson Franchise(s) Star Trek Creator(s) Akiva Goldsman, Alex Kurtzman, Jenny Lumet