10. Sugar Kane Kowalczyk (Some Like It Hot)
The Character: How to torment two guys in drag who need to keep their cover intact? A girl so sweet you can't help liking her... and sexy as hell singing 'I Wanna Be Loved By You' in a diaphanous gown. Some Like It Hot, indeed.
The Actress: Billy Wilder had suffered agonies while filming The Seven Year Itch trying to get Marilyn Monroe to remember her lines. But he still knew the effort of hiring Hollywood's biggest star was worth it.
The Performance: Monroe famously studied Method acting during the late 1950s, something that made her the butt of cruel Hollywood jokes. But she mined her troubled personal life to add a tangible air of sadness to counterpoint her exquisite comic timing.
9. Hildy Johnson (His Girl Friday)
The Character: Anybody who knows classic play The Front Page, where Hildy's fast-talking reporter is a man, is in for a shock. In the best change-to-a-remake ever, in His Girl Friday Hildy's editor Walter Burns is also her ex-husband.
The Actress: Rosalind Russell was furious that Howard Hawks asked half a dozen actresses to play the role before her... Fortunately, that's the attitude Hawks was after.
The Performance: Russell, afraid her dialogue wasn't as good as co-star Cary Grant's, hired a writer to beef up her lines. So when Hawks encouraged ad-libs, she's already perfected her hundred-word-a-minute zingers.
8. The Bride (Kill Bill)
The Character: Take the battered archetype of countless rape-revenge horrors, give her the fighting spirit of martial arts movies, the laconic amorality of Spaghetti Westerns, and a very cool yellow tracksuit... and voila.
The Actress: Uma Thurman began creating her Kill Bill character with Quentin Tarantino on the set of Pulp Fiction, so this decision never even got as far as a casting director - despite the wasted potential (Batman and Robin, The Avengers) in the interim years.
The Performance: Thurman's statuesque figure and wry death-stare made compelling action a given. What was more unexpected was the subtlety with which Thurman stripped away The Bride's iconic poise to reveal the tragic, vulnerable figure of Beatrix Kiddo beneath.
7. Hermione Granger (Harry Potter series)
The Character: A clever clogs whose intelligence helps her do cool tricks with a magic wand, Hermione is this generation's finest girl-geek. Don't believe us? Give it ten years, and Hermione will be even higher up this list.
The Actress: Hundreds auditioned, but stars will out. So it was that nine-year-old Emma Watson, without a professional credit to her name, bagged the role of her short lifetime.
The Performance: We've all seen Hermione grow up thanks to Watson, and that brings layers Rowling never dreamed of. Who would have thought the precocious kid of ten years ago would become the remarkable woman who brought such tender realism to The Deathly Hallows: Part 1?
6. Dorothy Gale (The Wizard Of Oz)
The Character: The girl who dreams of getting away from boring sepia reality and is duly whisked away into a Technicolor fantasy... only to get there and realise maybe, actually, there's no place like home. We've all been there, right?
The Actress: Child star Judy Garland was only second choice for The Wizard Of Oz (behind Shirley Temple) but the role defined her all the way to her tragic early grave.
The Performance: Wide-eyed with wonder, Garland roots the craziness - Munchkins! Scarecrows! Flying monkeys! - with homely grace and sincere emotion. Dorothy could so easily get lost in the mix, but be honest: Garland has you hooked from the first notes of 'Over The Rainbow.'
5. Princess Leia Organa (Star Wars)
The Character: Royalty turned revolutionary, a capital-L Lady with a laser gun in her hand and a soft spot for rogues. Cool, even before you know she also has Jedi blood.
The Actress: Plenty of great actresses auditioned but there's a pleasing symmetry in the fact that novice Carrie Fisher was hired at the same age (19) her mother Debbie Reynolds was cast in Singin' In The Rain.
The Performance: Unlike the shrinking violets of B-movie sci-fi, Fisher's Princess won't get shit from anybody. Probably the fire is the actress' reaction to the indignity of having to put her hair into bagels and tape down her breasts. Her eventual reward? Flowing locks and a metal bikini.
4. Clementine Kruczynski (Eternal Sunshine Of The Spotless Mind)
The Character: Rainbow-haired kook so impulsive she'll commit to wiping the memory of a bad romance, but so free-spirited she'll fall in love all over again to enjoy the Eternal Sunshine Of The Spotless Mind.
The Actress: Kate Winslet was already probably the great dramatic actress of her generation. Michel Gondry took one look, ditched the corset, dyed her hair and got her to funny up.
The Performance: A liberated Winslet gives more of herself to Clementine than any other role. Probably because, for once, the Titanic gal is waving not drowning. Her sheer force of personality turns Jim Carrey's memory wipe into an existential hell.
3. Sarah Connor (Terminator)
The Character: Mulleted suburbanite, or heroine of the revolution? Amazing the effetimey-wimey shenanigans with a robotic killer and a hot stud from the future will do.
The Actress: Children of the Corn predated The Terminator, but Connor was the role that pushed Linda Hamilton into sci-fi aristocracy and a regular gig opposite Ron Perlman on TV's Beauty and the Beast.
The Performance: "Are you Sarah Connor?" By the end of The Terminator, Hamilton has left no doubt she's the legend of Earth's post-apocalyptic future. Even so, it's punch-the-air time when we find out just how bad-ass she's become in T2: Judgement Day. Sorry, Lena Headey.
2. Annie Hall (Annie Hall)
The Character: The ultimate 'one that got away,' Annie's ditzy charm and Boho chic make her the most idealistic - but still realistic - of romcom women.
The Actress: A no-brainer. Not only was Diane Keaton Woody Allen's one-time lover and regular co-star, but he named the part after her (she was born Diane Hall).
The Performance: Woody Allen had originally intended to make a three hour drama called Anhedonia, but it quickly became clear that Keaton's charisma was driving the film into a tenderer, more romantic direction. The Academy agreed: Best Actress was in the bag.
1. Ellen Ripley (Alien)
The Character: Survivor. Warrior. Saint. Mother. Woman.
The Actress: Ripley Scott needed a relative unknown capable of becoming the surprise heroine when her Nostromo crewmates got chomped. The sets were still being built when Sigourney Weaver, with only a fleeting role in Annie Hall on her film C.V., wowed during screen tests.
The Performance: Weaver brought both Hawksian toughness and feminine vulnerability to Ripley, but the real greatness came later. Never has a female character grown so much, over so many films - something acknowledged when Weaver earned an Oscar nomination for Aliens.