Film historians will look back at this film and call it a game-changer. Cameron has done it again, but this time he has taken it to the next level by actually creating a plausible biosphere for another planet populated with a diversity of creatures for various ecological niches that would make any evolutionary biologist smile. A long movie that never feels long -- the plot, the acting, the effects are all extraordinary. Warning: if you support American marines murdering people indiscriminately to further our national goals, you will probably object to the theme of this film.Don't miss this one! I can't imagine anyone watching this film and not saying: "WOW!" when it's over.