Nele, alienígenas liberam gases de efeito estufa na atmosfera para aquecer a Terra e matar a humanidade.
Zane discovers the plant doubles as a front for an underground alien base. The very different looking aliens are able to disguise themselves with an external skin to infiltrate human society. Zane finds that all of the bases expel large amounts of greenhouse gas into the atmosphere. Zane is discovered but escapes back into the nearby town and attempts to convince the local sheriff of the situation. However, alien agents bring Ilana's body to the police station, making Zane a suspect in her death; Zane escapes and sneaks back into the United States. He accosts Phil on the JPL grounds, forcing him to admit that the aliens are trying to raise the Earth's temperature to not only kill off humans (by greatly exacerbating anthropogenic climate change) but to make the planet hospitable for themselves. Zane secretly records the conversation and once Phil discovers the recording he sends agents to stop Zane.
Wikipedia, The Arrival (1996 film)
O resumo da Wikipedia também menciona as pernas que se dobram para trás:
they watch as Kiki's legs form into a shape similar to that of backward kangaroo legs, then runs off.
E se esta imagem estiver correta, eles se parecem com isso:
O pôster não corresponde exatamente ao que você diz, mas há o reflexo nos olhos e o brilho laranja. Eu acredito que existem variantes diferentes disso com os objetos em perspectivas diferentes, mas o tema geral é o mesmo.
