Revealing mistake: As Kurn is chastising Worf in the infirmary, the actor's prosthetic nose has become detached from the rest of the Klingon make up. You can see the nose wobbling around as he talks.
Broken Link - S4-E26
Revealing mistake: During the fight between Garak and Worf near the end of the episode, a Jefferies tube door is knocked out of its frame to reveal the end of the set - a dark room with a wooden scaffold and various other pieces of equipment. (Slow-mo helpful but not required)
Revealing mistake: In episode 'The Passenger', when the Koblian officer opens Vantika's eyes to run a retinal scan, his pupils dilate, despite the fact that he is dead.
A Simple Investigation - S5-E17
Revealing mistake: When Odo and Arissa are talking in Odo's quarters, you can see where the star field ends and where the sound stage floor begins.
Revealing mistake: Clear use of a stunt double for Avery Brooks during the brief tussle with Dax in the holding cell.
Revealing mistake: As Sisko and Omet'iklan are arguing in the Mess Hall, the dead Jem'Hadar solider can be seen breathing. His chest is seen moving up and down. (00:30:35)
Revealing mistake: When the Lakota opens fire on the Defiant, steam begins pouring into the Defiant bridge. The device releasing the steam is visible.
The Way of the Warrior (2) - S4-E2
Revealing mistake: During the fight in Ops, the laws of physics takes a slight dive. While Worf is fighting the Klingons, he hits them with his Bat'leth or his mek'leth, and a second later they react to the hit.
Answer: Worf: Curzon's name is an honored one among my people. Dax: (in Klingon) Yeah, but I'm a lot better looking than he was.
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