Hidden is a fantastic movie, but the ending is silly. When Kyle MacLachlan's alien moves to Michael Nouri's body, he becomes some kind of stupid new-age shinny light. It should be another disgusting slimy creature like the villain. Aren't they from the same species?
shareSaw it again last night, I think it's not clear if both are from the same planet, but we can see their species are kind of different.
EDIT:
I have not seen the second film, but I just read part of the plot in wikipedia, and the plot explains the difference in the good aliens and bad aliens:
"It is explained that on the alien's homeworld, evolution took two parallel paths: half of their race became violent criminals who live only for pleasure (the squid-like alien form briefly glimpsed in the first film), and the other half evolved beyond their base desires and even physical bodies, becoming creatures of pure energy. "
Maybe the second film is not so good, but that's a very clear explanation.