designed to enable the clearing of McChesney's airways quickly should there be a problem, no oxygen tank was included in the construction and so he had to hold his breath whilst under the surface of the oil. Crewmembers kept track of the length of time he was under by using a stopwatch. The oil itself was a water-soluble Metamucil material which was dyed black using printer's ink. During production the crew found that for some reason the liquid kept dissolving the seams of the suit, although the head was unaffected. A backup suit had been ordered before production began at the last minute, and was required in order to shoot all the scenes. After they started to break apart, further orders were placed for additional suits and all the suits used eventually fell apart during the four days they were used on set. In order to film one scene, McChesney wore the suit open-backed due to the damage. No optical effects were used in creating Armus. For the scene where Riker is pulled into the oil, a stuntman was used as a stand in for Jonathan Frakes. Where Riker's face emerges from the oil, it was actually a plaster cast of Frakes' face painted black. It was placed on the same grate used to lift McChesney, and filmed lifting out of the liquid. The twitching effect in Yar's death was due to a wire tied around Crosby's waist being pulled on. Reception "Skin of Evil" aired in broadcast syndication during the week commencing April 29, 1988. It received Nielsen ratings of 9.7, reflecting the percentage of all households watching the episode during its timeslot. This was a decrease of 1.1 ratings points from the previous episode, "Symbiosis", and was the same ratings level received by the following episode, "We'll Always Have Paris". Several reviewers re-watched Star Trek: The Next Generation after the end of the series. Zack Handlen for The A.V. Club gave the episode an overall score of C−, saying that at points the episode just got annoying especially when Troi was describing Armus' feelings. He thought that Yar's death scene was out of place in the episode and that overall Armus was unthreatening, saying "Murdering Yar should make Armus seem much more dangerous, but he's just so whiny and petulant and bland that he could've killed half a dozen cast members without leaving an impression." Keith DeCandido for