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A Look Back at 'Skin of Evil'

On its 35th anniversary, we revisit the episode's production as well as Armus' first appearance!

Illustrated banner featuring Armus in his first appearance on Star Trek: The Next Generation and his latest appearance on Star Trek: Lower Decks

Few episodes of Star Trek: The Next Generation are as controversial and divisive as "Skin of Evil," which premiered on television sets on April 25, 1988.

On its 35th anniversary, we're revisiting the episode that has stoked plenty of debates over the decades, which continues to this day, ranging from Armus' first appearance, the death of Lt. Tasha Yar (and actress Denise Crosby's exit), and The Next Generation's first season in general.

The Malevolent Entity Armus

"I do not serve things evil. I am evil." — Armus

Close-up of Armus taking a humanoid-form in 'Skin of Evil'

"Skin of Evil"

Armus is the embodiment of all that was negative and destructive of Vagra II and the literal byproduct of their "skin of evil." The former natives of the planet, the Vagrans, expunged every undesirable emotion and negative attribute they possessed. While they became "creatures whose beauty now dazzles all who see them," their second skin manifested into the "dank and vile," unwanted substance known as Armus.

Despite resembling a living oil slick, Armus is able to alter forms into a variety of shapes, including a humanoid-like form and a thin shielding large enough to envelop a Galaxy-class starship's shuttle. Its formidable energy fields can affect passing vessels, or nearby people.

Data's tricorder could not detect any skeletal or cellular structure among the viscous pool of black liquid substance; Armus' dormant state. Its rage was what allowed it to generate energy fields. In addition to that, Armus was capable of thought, psychokinesis, teleportation, and energy discharges. Armus found pleasure in torture those it was able to lure into its pit of evil.

The Making of Armus

"Save your compassion; it's revolting. You offer it like a prize, when, in fact, it's an insult."
— Armus

In front of his crewmates, Riker is pulled into Armus' pit of evil in 'Skin of Evil'

"Skin of Evil"

Armus was played on set by Mart McChesney, who later portrayed Sheliak in "The Ensigns of Command," and voiced by Ron Gans.

During this year's Star Trek: The Cruise, on the Star Trek: The Next Generation panel, actor Jonathan Frakes (William Riker) brought up "Skin of Evil" during his discussion with fellow castmates, Denise Crosby (Tasha Yar), Brent Spiner (Data), Marina Sirtis (Deanna Troi), and John de Lancie (Q).

In the episode, during a fit of rage, Armus pulls Riker into its liquid state, enveloping him along with previous Starfleet crash survivors. Armus' victims are incorporated into its liquid state where they remain conscious as it inflicts suffering upon them, an act spurred by boredom that Armus uses to amuse itself.

Speaking on filming the scene, Frakes noted, “The black slime. No one, especially present company and Levar [Burton] and [Michael] Dorn, nobody would actually get in this pile of shit. It was 100 gallons of Metamucil dyed with black printer’s ink. The only one in there with me, Wil Thoms; he was our special effects guy.”

Commenting on the production, Spiner quickly addressed Frakes, “There was an upside too. You’ve been completely regular ever since.”

Riker's anguished face as he's enveloped by Armus' liquid state in 'Skin of Evil'

"Skin of Evil"

The April 2002 issue of Star Trek: The Magazine detailed that series makeup artist and supervisor Michael Westmore designed Armus' head while the costume was made by Makeup & Effects Laboratories. Westmore stated there was a potential additional ingredient in the black slime created by the series' special effects department, "It was a combination of printer's ink and a water-soluble gel, but I don't know what else was in it because it caused the glue in the costume — very strong shoe glue — to undo itself, and the costume would fall apart so we would need a new costume for the next day."

Crosby recounted the "difficult" production for back in 2012, "They way they rigged that rubber suit, the actor [playing Armus] had to literally be submerged into and out of that muck. That had to work within a minute because he had no oxygen in that suit. That’s no special effect. You saw him literally come up out of this muck, and it was very hot and really dangerous."

The Death of Lt. Tasha Yar

"I would guess that death is no longer sufficient to alleviate its boredom."
— Data, on Armus

Data, Beverly Crusher, and Riker surround Tasha Yar's lifeless body in 'Skin of Evil'

"Skin of Evil"

In addition to Armus' first appearance, the episode is most known for Armus' brutal killing of Lt. Tasha Yar at the start of the second act, where she is quickly hit with an energy blast from Armus and instantly killed.

Yar's storyline came to its conclusion in the first season due to actress Denise Crosby's request to be released from her contract as she was not happy with her character's development and was eager to pursue other opportunities. Gene Roddenberry obliged and Yar died in a sudden and unsentimental manner, in the line of duty.

In a 2012 interview with, Crosby noted that she made the right decision leaving the series, stating, "For me, I was miserable. I couldn’t wait to get off that show. I was dying. This was not an overnight decision. I was grateful to have made that many episodes, but I didn’t want to spend the next six years going 'Aye, aye, captain,' and standing there, in the same uniform, in the same position on the bridge. It just scared the hell out of me that this was what I was going to be doing for the next X-amount of years. I think you have to take your chances."

Many fans felt that Yar deserved a far better send-off, with most of them deeming Armus a silly adversary that cheapened Yar's already lackluster demise. On the other hand, there are those fans who appreciated the fact that Yar died as many people do, on the job and without warning, with no departing words.

In the same aforementioned interview, Crosby shared her views, "What I’ve always gotten from fans was, 'What a weird way to kill one of your main characters.' It was so indiscriminate, without a fight, without any confrontation or battle. This thing just takes her out. Then, when I came back for 'Yesterday’s Enterprise,' there was some sort of redemption there."

A hologram of Tasha Yar playing a video message at her funeral in 'Skin of Evil'

"Skin of Evil"

"Hello, my friends. You are here now watching this image of me because I have died. It probably happened while I was on duty, and quickly, which is what I expected. Never forget I died doing exactly what I chose to do."
— Tasha Yar

In actuality, Yar did utter final words, saying goodbye to her beloved crew (and fans) via a hologram played during a tearful memorial service in the holodeck.

However, this would not be Crosby's final Star Trek appearance, as she would return to The Next Generation as Yar, in an alternate timeline, and Sela, the half human, half Romulan daughter of the alternate universe Tasha Yar.

Current Star Trek Connections

"When I find you, I'm gonna kill you with a flake of my power! I am a skin of evil!"
— Armus, "The Spy Humongous"

Star Trek: Lower Decks - Prank Calling

The influence of "Skin of Evil" continues on in current day Star Trek. In Star Trek: Lower Decks' second season "The Spy Humongous," with Shaxs' submanifold casting stone, the lower decks crew aboard the Cerritos prank calls Armus, who is still stuck on Vagra II, bored and in need of someone to torture.

While in the third and final season of Star Trek: Picard's episode "Surrender," as Data and Lore battle over control of their positronic body, Data willingly hands over his priceless memories to Lore, which includes a holocube of Tasha Yar.

"Skin of Evil" Fast Facts

Armus faces Riker, Data, and Tasha Yar in 'Skin of Evil'

"Skin of Evil"

  • The episode, like the creature, was originally called "The Shroud."
  • "Skin of Evil" was conceived by screenwriter Joseph Stefano, who co-wrote the teleplay with Hannah Louise Shearer.
  • Armus was named after the first season's writer and producer, Burton Armus.
  • The episode was marked as the first time Star Trek had killed off a series regular.
  • The filming of Tasha Yar's memorial service emotionally affected the cast; to lighten the mood on set as they headed to the grassy knoll for the scene, Patrick Stewart sang The Sound of Music's "The Hills Are Alive."