Another instance that strikes up fervent debate, there's simply no doubting that Ridley Scott's Alien and James Cameron's Aliens are both stunning films and easily the best entries into the entire franchise. Deciding what's the better of the two get a little dicey, though; the first is slower and a more deliberate horror suspense film, whereas Aliens is a full-tilt action movie with fetishised weaponry, larger-than-life characters, and perhaps surprisingly, a whole lot of heart as well. Though I love Alien, for me Aliens just about clinches it; the beefy action sequences notwithstanding, the film makes an extremely concerted effort to develop Ripley (Sigourney Weaver) as a human being. Particularly in the Director's Cut, we're able to feel the disconnect she has due to the death of her daughter while she was in stasis, and how this transpires through to the touching maternal bond she has with young colony survivor Newt. So well-received was Weaver's performance that she ended up being nominated for a Best Actress Oscar, a milestone in this science-fiction and action genres that has yet to be met.