Continuity mistake: Early in the movie the female protagonist "Lex" Woods is climbing an ice waterfall. The scene shown from a distance reveals a steep ascent above the ice, but in the next scene, she reaches a large area flat enough for a helicopter to land upon. (00:03:40)
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Alien Vs. Predator (2004)
Ending / spoiler
Directed by: Paul W.S. Anderson
Starring: Lance Henriksen, Ewen Bremner, Sanaa Lathan, Colin Salmon, Raoul Bova
Lex and the remaining predator make it to the surface. The predator then marks Lex's face with the symbol of the predator. The Queen alien breaks through the ice and she is killed by Lex and the predator by being tied to a big silo at the abandoned whaling station and pushing it and the queen into the freezing water below. But, before she dies, she impales the predator with her tail. Lex goes to the predator's aid and he dies. The predator space ship comes to claim the body and the lead predator gives Lex a sword. On the predator space ship, the new Predalien chestburster comes out of the dead predator. The end?...
Cady
Alexa 'Lex' Woods: How do you say "scared shitless" in Italian?
Sebastian de Rosa: Non vedo l'ora di uscire da questo piramide con te, perché mi sto cagando addosso. More or less.
Question: Can anyone tell me why the Predators didn't scan the 'token' human survivor or the last dead predator to see if either were infected with an Alien? Especially when the Predator was not wearing his face mask which would serve as protection against this infection.
Chosen answer: Given the speed with which the chestbursters emerged from the other humans, it seems likely that these have been engineered by the Predators to emerge as quickly as possible. As such, they probably assumed in Lex's case that, were she impregnated, it would have emerged before that point. As for their fallen comrade, it may well have simply not occurred to them that one of their number would be foolish enough to get himself impregnated. Even proud alien hunters can make mistakes.
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Answer: When they emerged from the underground pyramid unscathed, the Predators assumed they were not infected. Any Predator, young or old, would have been taught to self destruct rather than be caught or killed. As seen in the previous movies. Lex was given the mark of a warrior, they assumed she was taught their code of honor.