Revealing mistake: When the bridge is exploding from the mine attack, the stuntman playing Jason obviously launches himself out of the captain's chair.
Revealing mistake: When Saris is torturing the Thermian commander, he stops and approaches Commander Taggart; while Saris is talking to Taggart you can see the lips and teeth of actor Robin Sachs behind the mask.
Revealing mistake: When General Roth is threatening Jason with his claws wrapped around Jason's throat, the very moment he tilts his chin back, you can see the actor's open mouth and teeth visible inside, though he's supposed to be an alien enemy.
Answer: Dane is a classically trained stage actor from England. On the stage they have the saying "The show must go on". i.e. hundreds of people have payed for tickets to see the play, so the thespians go on stage to do the best job they can. Nesmith is reminding Dane of this as Dane considers it a stage tradition that he doesn't want to break.
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