2. Katie Holmes - Meh
The one time Mrs Tom Cruise wasn't given too much of an opportunity to dazzle in Batman Begins, since the role of Rachel Dawes was invented as a symbol and a moral compass for the occasionally wayward Bruce Wayne, but that doesn't excuse the fact that she proved herself woefully under-equipped to play such an important narrative role. The key to any character who is little more than a plot device is for the performance to be memorable enough to hide the agenda: Michael Caine managed it with Alfred, despite the fact that pretty much every one of his lines could be taken out of The Little Book Of Paternal Reassurance (or The Little Book Of Exposition in the case of The Dark Knight Rises,) but Holmes' performance was one-dimensional and cold, and it's near impossible to understand why she is the centre of Bruce's moral and emotional world. By the time Rachel dies (albeit in the hands of another, far superior actress) it's still difficult to really care, which makes Batman's decision to retire for eight years on the back of the tragedy that little bit more difficult to take. That all stems from the fact that we aren't given enough development of the character in Begins, or enough sparkle in the performance to make her anything other than a walking, talking plot device.