Inspired casting (and makeup)
During the film I was struck by how alike Judi Dench and Kate Winslet looked - then I started wondering what Iris Murdoch had really looked like. Have a look at these and tell me the choices of Winslet and Dench, and also Jim Broadbent, weren't as close to perfect as you can get:
Older Iris: http://www.zenunbound.com/graphics/murdoch.jpg
Younger Iris: http://www.leksikon.org/images/murdoch_iris.jpg
Older Iris and John Bailey:
http://www.famous-couple.com/pics/iris_murdoch-john_bayley.jpg