No Star Trek alien has undergone as many changes as the Klingons, and here's every variant featured in the franchise. Although they were the main villain in Star Trek: The Original Series, it wasn't until the movies that they adopted the iconic look that continues to define them to this day. The change from flat foreheads to cranial ridges and long hair has inspired various writers over the years to try squaring the inconsistency in canon, which only complicated matters further.
Given that the Federation is an intergalactic melting pot of cultures, it's unsurprising that Klingons mate with partners from outside their species. There have been several interspecies variations of Klingon, most notably Star Trek: Voyager's Lieutenant B'Elanna Torres (Roxann Dawson), who was the daughter of a human father and Klingon mother. Genetic experiments have also created some fascinating variations on Klingon DNA, making them one of the most diverse Star Trek species. Here's every type of Klingon to appear in Star Trek so far.
12 TOS Klingons
The Klingons first appeared in Star Trek: The Original Series season 1, episode 26, "Errand of Mercy". Actor John Collicos, who played Kor in the episode, was the first TOS Klingon, and is largely responsible for their look, and the depiction of them as conquerors. Collicos took inspiration from Genghis Khan, which made the Klingons a more universal foe than the communist analogs they were originally intended as. It's clear to see the influence of Khan on Collicos' look, and on future portrayals. The long moustache, and the calculating military mind that was belied by a tendency for savagery is what defined each of the main 3 TOS Klingons.
11 TNG Klingons
The Klingons got a significant upgrade for 1979's Star Trek: The Motion Picture, which kept the facial hair but gave them longer hair, more identifiable warrior's armor, and the forehead ridges that would become their trademark. Finally, it was Star Trek: The Next Generation that would polish this look and create the iconic version that endures to this day. Rather than the strange bumps and lumps that were seen on the Klingons in Motion Picture there were proper ridges on the TNG Klingons. The fact that Lieutenant Worf (Michael Dorn) was a Klingon allowed Star Trek to explore the internal society of the Klingon Empire in ways it had never done before.
10 Star Trek: Enterprise’s Klingon Augments
"Broken Bow" revealed that the very first mission for the Enterprise NX-01 was to return a wounded TNG-style Klingon warrior to Q'onoS. In Star Trek: Enterprise season 4, the show attempted to explain the forehead disparity between the TOS and TNG Klingons. The answer was a genetic mutation caused by experiments with creating Augments, like the ones created by Dr. Arik Soong (Brent Spiner). The mutation resulted in more humanoid Klingons, erasing their forehead ridges and changing their personalities to be more in line with the original TOS versions. A cure was found and the smooth headed Klingons continued to serve the Empire into the 23rd century.
9 Star Trek Into Darkness’ Klingons
The Klingons in Star Trek Into Darkness had bald heads, pierced cranial ridges and also wore a different style of armor. The Kelvin Klingons wore helmets, which felt superfluous given how robust Klingon foreheads supposedly were. The other difference was that the Klingons in the Kelvin timeline felt more secretive and mysterious, like the Romulans in the classic TOS episode "Balance of Terror". Their secretive nature meant that war with the Klingons had not yet taken place in the Kelvin Timeline, whereas in the Prime Timeline, the war had taken place years earlier, as depicted in Star Trek: Discovery.
8 Discovery Klingons
The controversial Klingon redesign overshadowed the many positives of Star Trek: Discovery season 1. Although they retained the cranial ridges and warrior's armor they were shorn of their TOS-style facial hair and TNG-style long hair. These differences could have been explained by Discovery's villain T'Kuvma (Chris Obi) who wished to return to a more traditionalist way of life. While that explained the more brutal behavior, it didn't explain the substantially different look. The Klingon controversy meant that the classic Star Trek aliens have been largely absent from the live-action shows, until the return of Worf in Star Trek: Picard and Star Trek: Strange New Worlds' Klingon episode in season 2.
7 Albino Klingons
In Star Trek: Deep Space Nine season 2, episode 19, "Blood Oath", three TOS Klingon warriors teamed up with Lieutenant Jadzia Dax (Terry Farrell) for a revenge mission. Jadzia was fulfilling a blood oath between the Dax symbiont's former host Curzon and Kor, Kang, and Koloth to seek vengeance against The Albino (Bill Bolender). Although Klingon in appearance, the pale-skinned villain with white hair was markedly different from other of his species, which perhaps explained his status as a fugitive from Klingon justice, and his hatred for the species. Interestingly, the script for "Blood Oath" didn't describe The Albino as a Klingon, only describing him as "an all-white humanoid".
Star Trek: Discovery seemingly confirmed The Albino's Klingon status by introducing two more albino variants in seasons 1 and 2. Voq (Shazad Latif) was ostracized by Klingon society for his albinism, but eventually rose to prominence by proving his worth to T'Kuvma and vowing to defend his legacy. In Discovery season 2, Captain Christopher Pike (Anson Mount) encountered Tenavik (Kenneth Mitchell), who was the son of Voq, and was raised on the planet Boreth. Thanks to the time crystals on the planet, Tenavik had swiftly become an adult, and negotiated with Pike for the use of the temporally charged mineral.
6 Bald Klingon
Prior to Star Trek: Discovery's bald Klingons, Star Trek VI: The Undiscovered Country had already introduced General Chang (Christopher Plummer). However, Chang's baldness was an exception, rather than the rule that was established for Discovery. The reason for Chang's baldness was purely a request by the actor Christopher Plummer, who requested to have as little Klingon make-up as possible. Plummer got his wish - Kang's ridges are less pronounced, his mustache is more neatly trimmed, and the flowing hair of a Klingon warrior is shorn from his head.
5 Klingon/Human Hybrid
As well as Star Trek: Voyager's B'Elanna Torres, there are other notable Klingon/Human hybrids in Star Trek canon. B'Elanna's daughter Miral Paris is a quarter Klingon, while Worf's son, Alexander Rozhenko was a quarter human. Alexander's mother was K'Ehleyr (Suzie Plakson) the daughter of a human mother and Klingon father, who struggled with coming from two vastly different cultures. It's no surprise, therefore, that she found a soulmate in Worf, a Klingon who was raised by his adoptive human parents Sergey and Helena.
4 Klingon/Trill Hybrid
In the Star Trek: Deep Space Nine episode "Children of Time", the crew of the USS Defiant discover a planet inhabited by their own descendants. The civilization was a result of a temporal accident which left the Defiant crew marooned 200 years in the past. Among the descendants is Brota, a Klingon/Trill hybrid descended from Worf and Dax, who decided to live life as a Klingon, with the Sons of Mogh. When the Defiant avoided the accident, the timeline was erased, along with the crew's descendants.
3 Klingon/Romulan Hybrid
In "Birthright", Worf discovered an isolated colony on Carray IV, where Klingons and Romulans lived peacefully together. The concept horrified Worf, who was forced to confront his anti-Romulan prejudice when he became attracted to Ba'el (Jennifer Gatti) a half-Klingon, half-Romulan woman who lived at the former prison camp. Ba'el was the daughter of a Romulan father, Tokath (Alan Scarfe) and Klingon mother, Gi'ral (Cristine Rose). Worf's arrival on Carraya IV risked revealing the truth of the colony to the wider Romulan and Klingon Empires, but despite his distaste, he agreed to keep its location a secret, ensuring the safety of Ba'el and her fellow colonists.