I'm not sure I understand the wisdom of filming a story about Casanova (Heath Ledger) and then filling its 108 minutes with scenes of the great lover assuming false identities to avoid church censure and being one-upped by an independent woman (Sienna Miller) in other words, doing everything other than being Casanova. Maybe Touchstone Pictures thought that too many shots of their hero hopping in and out of bed and servicing nuns (!) would lose them the female audience. But those naughty bits sure seemed to tickle the imaginations of the ladies at the screening I attended. (Think twice until you see Brokeback Mountain, girls. You don't know where Ledger's lips have been.) Pleasantly undistinguished, this movie rests on a handful of crowd-pleasing plot points about true love, and on a few strong supporting turns: Oliver Platt, who plays an obese Genoan fop, has now saved two movies in as many months.