There’s no question that the Stargate franchise shares some DNA with Star Trek — fun, adventurous, sometimes dramatic science fiction. That’s especially true of the Trek shows that were in production in the 1990s and early 2000s, when Stargate SG-1 and Stargate Atlantis were also filming.

But did you know that these two beloved sci-fi franchises also share a whole lot of actors? Although Star Trek filmed in California and Stargate in Canada, a surprising number of main cast members crossed over. And what Stargate fans got was an array of amazing and original characters, played by some of our favorite actors.

This was never “stunt casting.” As we’ll see in the list below, these actors were perfectly cast for the roles they played on Stargate.

Before you scroll down to see the complete list, let’s make a game of it: How many can you name? Are you the sort of viewer who leans forward and points at a familiar actor the moment they turn up … or do you only realize later who the actor was?

Here are a few hints if you want to try and name them all before looking below:

• We’re talking strictly about Star Trek’s regular cast members — not recurring guest stars, no matter how many episodes they did or how beloved they are. (Read: Yes, we know “Q” actor John de Lancie played Colonel Simmons!)
• Just one of these nine actors was a regular on The Next Generation. DS9 has the most, with four cast members.
• None of them are cast members on a modern-era Trek show.
• Three of the nine might be harder to recognize, because one of their roles was under heavy prosthetics.
• One, and only one, of these actors also became a regular cast member on a Stargate show!

Let us know in the comments below how many you remembered, and which of their Stargate characters was your favorite!

ARMIN SHIMERMAN

On Star Trek: Quark (Star Trek: Deep Space Nine)
On Stargate: Anteaus (Stargate SG-1‘s “The Nox”)

Stargate got its very first Star Trek actor crossover early on in its first season. SG-1 visits a forested planet (there are a lot of those) on the hunt for a flying creature with the power of invisibility. They encounter the evil Apophis himself, also on a hunt with his royal guard. The team plans to ambush and capture the System Lord — which goes horribly wrong. After being shot dead, the team awakens to meet a race of people who have brought them back to life.

“Quark” actor Armin Shimerman plays Anteaus, a leader among the Nox. They were eventually revealed to be not primitive forest dwellers but one of the oldest and most advanced races in the galaxy, once allies with the Asgard, the Furlings, and the Ancients themselves. In the very memorable closing minutes of the episode Anteaus reveals the Nox’s great floating city, reassuring SG-1 that they need not fear that the Goa’uld will come for the Nox. The Nox can take care of themselves.

RENE AUBERJONOIS

On Star Trek: Odo (Star Trek: Deep Space Nine)
On Stargate: Alar (Stargate SG-1‘s “The Other Side”)

Shimerman’s DS9 co-star, the late Rene Auberjonois, played a very different role in his Stargate guest appearance. In this fourth-season episode Stargate Command receives a plea for help from a people on the losing end of a world war. When SG-1 visits they meet Alar, leader of the Eurondans, who are willing to trade all of their advanced technologies in exchange for help turning the tide of their conflict. But they don’t need weapons or soldiers — only heavy water to power their generator.

The casting here is brilliant: Auberjonois is someone that viewers want to like, but despite Alar’s sincerity it’s clear that something is not quite right with him. Jack is ready to make a deal but Daniel pushes back, insisting that they learn more about the Eurondans’ enemy. In the end they discover that their new ally not only started the war, but are Nazi-like white supremacists bent on wiping out “Breeders” for their lack of genetic “purity.”

The deal is off, and with the facility crashing in around them Colonel O’Neill warns a desperate Alar not to follow them back to Earth. He steps through the gate and orders the iris closed.

MARINA SIRTIS

On Star Trek: Deanna Troi (Star Trek: The Next Generation)
On Stargate: Svetlana Markov (Stargate SG-1‘s “Watergate”)

We fell in love with her as Counselor Troi on The Next Generation, but on Stargate Marina Sirtis plays a very different character. Dr. Markov is a brilliant Russian scientist, the genius behind her country’s own secret Stargate program. The Russians scooped up a Stargate after an Asgard mothership crashed into the Pacific Ocean (“Nemesis”), and then conducted an off-world reconnaissance program out of Siberia for several weeks before things went horribly, horribly wrong.

SG-1 is called in when the Russian Stargate will not shut down. With Dr. Markov they reach the facility and find (almost) everyone dead. She then pilots a mini-submarine through the event horizon to make an incredible discovery amidst the submerged gate on the other side. And, with Sam and Daniel, she barely escapes with her life.

Sirtis brings a sharp and no-nonsense approach to Markov’s character, both able to go toe-to-toe with O’Neill (and with a wisecracking Jackson, for that matter) and showing how deeply she is affected by the grisly fate of her close friends and colleagues.

JOHN BILLINGSLEY

On Star Trek: Dr. Phlox (Star Trek: Enterprise)
On Stargate: Simon Coombs (Stargate SG-1‘s “The Other Guys”)

In Season Six Stargate SG-1 gave us its version of a “lower decks” episode, turning the camera on the ordinary scientists and geeks that keep Stargate Command functioning. Who is that in the background doing the nitty-gritty work when SG-1 is off on their next adventure? The stars of the show in “The Other Guys” are a great comedic pairing: Canadian national treasure Patrick McKenna (The Red Green Show) and Enterprise‘s John Billingsley (sans Phlox makeup).

Together they are Felger and Coombs, and after SG-1 is captured by the Goa’uld they sneak aboard the alien vessel to rescue them. Felger is a real fanboy who wants to be part of the team he idolizes. But the pair quickly discover that Colonel O’Neill and his team allowed themselves to be captured on purpose … and the scientists have just stumbled into a very dangerous plan.

It’s great fun to see another Star Trek veteran on Stargate — out of makeup, and this time as a member of the S.G.C.! Coombs also gives a shout-out to Star Trek creator Gene Roddenberry, and reveals his proclivities toward Vulcan cosplay.

It’s just a shame that when Felger returned in “Avenger 2.0” Coombs wasn’t with him for another accidental adventure.

JOLENE BLALOCK

On Star Trek: T’Pol (Star Trek: Enterprise)
On Stargate: Ishta (Stargate SG-1‘s “Birthright,” “Sacrifices”)

When it came time for series co-star Christopher Judge to write his own Teal’c episode, it was bound to focus on Jaffa culture … and feature a beautiful love interest for his character. “Birthright” expanded Stargate’s lore by introducing the Hak’tyl, a tribe of fierce women warriors struggling under the oppression of the Goa’uld Moloc. Teal’c and the team must convince the Hak’tyl to stop killing their fellow Jaffa to secure symbiotes for their young girls, and instead to try another way.

The leader of the Hak’tyl is Ishta, and for this important role the show cast another Star Trek: Enterprise icon: Jolene Blalock. Clearly she had the gravitas to pull off this driven leader and her deep emotions, in many ways a real change from the Vulcan T’Pol (whose strong emotions were always there, but usually locked under her Vulcan composure). But put the actress in a long, blonde wig and she’s definitely harder to recognize!

Ishta proved to be a worthy foil (and love interest) for Teal’c, and the character returned a year later for “Sacrifices.” Once again, we would have loved to see more of her. (When the Free Jaffa eventually unite and form a new government in Season Nine, the Hak’tyl representative is Simone Bailly’s character Ka’lel.)

ROBERT PICARDO

On Star Trek: The Doctor (Star Trek: Voyager)
On Stargate: Richard Woolsey (Stargate SG-1 and Stargate Atlantis)

Let’s say this right up front: Robert Picardo is a special actor. Major roles from Dr. Dick Richard on China Beach to Coach Cutlip on The Wonder Years, Voyager‘s Doctor on Star Trek and Mr. Woolsey on Stargate have demonstrated his incredible presence, his range, and (on occasion) that amazing voice. It was a real treat to Stargate fans not only to see him cast in a recurring role, but to then watch the character grow and mature and become a series regular.

Woolsey had an inauspicious beginning, sent in by the N.I.D. to investigate the death of a valuable member of Stargate Command in the seventh-season episode “Heroes.” He argued against SG-1 when the new president came into office (just begging the audience to hate him). But Woolsey soon realized that he was on the wrong side — in league with Ronny Cox’s Vice President Kinsey — and helped to take him down.

Richard went on to better things, representing the United States on the international panel put in charge of the Stargate program and the Atlantis expedition (the I.O.A.). He became a protagonist who had our team’s back, and grew from a coward to a leader willing to put himself on the line. Eventually Woolsey took charge of Atlantis as the expedition’s new leader, and the great Robert Picardo joined the main cast of Stargate Atlantis for its final season.

COLM MEANEY

On Star Trek: Miles O’Brien (Star Trek: TNG and Deep Space Nine)
On Stargate: Cowen (Stargate Atlantis‘s “Underground,” “The Storm,” and “Coup d’Etat”)

For years we loved him as Chief Miles O’Brien, who himself had an amazing arc from the bridge to the transporter room on The Next Generation, then over to Deep Space Nine as a series regular. We got to know about the dark corners of O’Brien’s past, and saw him working his blue-collar engineering job while growing a family. Colm Meaney played an amazing character.

When he was cast in an early episode of Stargate Atlantis, though, fans knew we were in for something very different. Sheppard’s team visits a seemingly peaceful, agrarian people called the Genii, who Teyla’s people have long known as friends and trading partners. Their leader is Cowen, who is somewhat gruff and stand-offish at first. But after the team discovers their secret underground city, the true nature of Cowen’s people is revealed: they are more advanced than they appear, and far more militant.

Cowen is the cut-throat leader of a militarized people, who have been rebuilding their once-great civilization in secret to avoid the next Wraith culling. They plan to strike back at the Wraith, and despite the overture of an alliance with Atlantis, the Genii are more interested in taking what they want than trusting anyone. Meaney plays the head-strong Cowen with aplomb, and he returned for two more episodes … leading to Cowen ultimately falling victim to the ambitions of his equally treacherous underlings.

CONNOR TRINNEER

On Star Trek: Charles “Trip” Tucker (Star Trek: Enterprise)
On Stargate: Michael (Stargate Atlantis, 10 episodes)

Stargate had one more Enterprise cast member to utilize, and it turned into a major, ongoing role. The script for Atlantis‘ second-season episode “Michael” has a great hook: the audience follows along with a young Lieutenant who awakens in the city unable to remember who he is. Michael Kenmore is surrounded by our main characters, who reassure him that he is one of their own — and they’re going to do everything they can to help him remember his life. But it’s clear to the audience that something suspicious is going on here, and maybe even our heroes cannot be trusted.

Connor Trinneer’s casting as a Wraith-turned-human is genius. Lt. Kenmore is a good ol’ down-home boy from middle America, seemingly innocent and upright to the core … or so we are meant to believe. So why does everyone seem to be hiding something from him? Why is Ronon so openly hostile towards him? Michael wonders, and we in the audience wonder right alongside him … until that fantastic reveal: Michael is a Wraith, whom the team captured and subjected to Dr. Beckett’s retrovirus to strip the Wraith DNA out of his genetic makeup.

What follows is a slow transformation back into his true nature, followed by three years of Michael as a ruthless villain who holds a personal grudge against Atlantis after he escapes. Trinneer appears in a whopping ten episodes of the show — and yes, there were plans to bring him back in a sixth season. (When the actor’s schedule prevented him from filming the Season Two finale “Allies,” Michael was played with prosthetics by Ferretti actor Brent Stait, but Trinneer voiced all the dialogue.) With so many ups and downs for Michael, his revenge schemes, and his own army of Wraith-human hybrids, Trinneer’s role is a masterclass in acting.

NICOLE de BOER

On Star Trek: Ezri Dax (Star Trek: Deep Space Nine)
On Stargate: Alison Porter (Stargate Atlantis‘s “Whispers”)

A late addition to the cast of Deep Space Nine is also the final entry in our list of Star Trek—Stargate crossovers. Nicole de Boer guest starred in the Atlantis Season Five horror episode “Whispers.” Sheppard’s team works alongside the all-woman team of Major Ann Teldy (Christina Cox), Captain Alicia Vega (Leela Savasta), Sergeant Dusty Mehra (Janina Gavankar), and Dr. Alison Porter (de Boer). The planet they are on is not only spooky because of all the fog … but also because of the terrifying creatures that Michael has created through his own twisted experiments.

Dr. Porter is the brains of her team — a whip-smart, young scientist looking for adventure out in the big, wide galaxy. Once again the casting is perfect here, as de Boer brings her signature charm of schoolgirl innocence and strength in the face of adversity. When the hybrids begin attacking people Porter is in the middle of the fight, hatching a plan to lure the creatures out into the open and wielding a P-90 alongside her teammates.

de Boer also has some great scenes with Paul McGillion, who plays Atlantis’s Dr. Carson Beckett. The two characters are clearly drawn to each other, and provide Dusty with some funny one-liners while they innocently flirt in front of her. Since Alison survived the episode and planned to return to Atlantis after some R&R back home, it’s a shame we didn’t get to see more of her.

So how many Star Trek actors on Stargate could you name? Did you get them all? Which of these characters was your favorite, and who did you want to see again? Let us know in the comments!

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