What Happens: A cross-transfer of human and alien DNA results in a slightly scary Ripley clone and – at the film’s climax – the birth of a giant half-baby alien thing with big sad eyes - who believes new Ripley is his mum.

Why It's Stupid: Because the alien is supposed to be the cold-hearted universe’s perfect killing machine, not a giant mewling toddler with soggy rubber skin and mangling claws. GET OUT into the dark vacuum of space, you franchise-murdering bastard!