Even if Heath Ledger were the only thing worth seeing in this movie, the movie would be well worth seeing. His performance in this sparkling farce is dashing and witty and altogether wonderful. It's light years distant from the tormented bisexual sheepherder he plays in "Brokeback Mountain," and it completes his emergence as one of the more gifted and versatile actors of his generation. (He's only 26.) Happily, there are many other things to recommend the picture as well.

The life of Giacomo Casanova (1725-1798) has been the basis of several earlier films, but possibly never before has it been recounted with such charm, spirit and surpassing visual beauty. Casanova is best-known, of course, as one of history's great lovers, although we have only his word for this. (He claimed to have liaised with 122 women over the course of his long life, but this assertion was made in the multi-volume memoirs he wrote in his dotage — apparently with no diaries to rely on — and is thus suspect.)

Whatever the case, it's hard to fathom how he could have found time for such marathon amatory activity. Born in the city-state of Venice, Casanova took a degree in law at the age of 17, entered and fled a seminary, served as an army officer and went on to become, at various times, a violinist, a spy, a papal knight, a swindling magician and a prolific novelist, essayist, playwright and translator. He knew Voltaire, Rousseau and Mozart. (He was present at the premiere of "Don Giovanni" in Prague in 1787, and claimed to have contributed to the opera's libretto.) He was an inveterate gambler, and the creator of the first national lottery, in France. He spread his seed with such abandon all over Europe that at one point, unknowingly, he nearly married his own daughter.

Thanks to a cleverly structured script by Kimberly Simi and Jeffrey Hatcher, the movie is able to ignore most of this, and to focus instead on the year 1753, when we find the already disreputable Casanova living in Venice under the protection of the city's chief magistrate, the Doge. In trouble for having an affair with a novice nun ("Well, hardly a novice," he protests), the young miscreant agrees to the Doge's demand that he find a wife and settle down. Adopting an assumed name, he chooses the virginal Victoria (Natalie Dormer), carefully neglecting to tell either her or her parents who he really is.

But a boy named Giovanni (Charlie Cox) is truly in love with Victoria, and he challenges Casanova to a duel. Casanova appears at the appointed time and place, but winds up crossing swords with another man — who turns out to be Giovanni's rebellious older sister, Francesca (Sienna Miller), in disguise. Francesca is secretly the author of a series of fiery, proto-feminist pamphlets, written under a male pseudonym, and they are the talk of the town. Casanova, unaware of this (he likes his women pliant), instantly falls in love with her. Francesca, however, is about to be married off against her will to a portly lard merchant named Paprizzio (Oliver Platt). No sooner has Casanova managed to head off this hapless character, however, than a Bishop Pucci (Jeremy Irons) arrives on the scene, determined to find Casanova and hand him over to the Inquisition to be punished for his dissolute ways. The Pope later puts in an appearance, and there's a fairly personable pig, as well.

The cast is expert in navigating all of this artful confusion. Jeremy Irons, in particular, with his sniffy officiousness, his ridiculous orange wig and his hands fluttering about like bony little birds, has never been funnier. (When he enlists Victoria's testimony against Casanova by promising to restore her reputation and her virginity, and she asks if he can really do that, he replies, "Oh, yes — we are the Catholic Church!") Oliver Platt is similarly vivid as the lovelorn lard merchant, sadly lamenting the fact that his only attraction for women is his "empire of pork."

The movie's most captivating appearance, however, is by the Most Serene Republic itself. "Casanova" was actually filmed in Venice, with considerable logistical difficulty. It's a city in whose palazzos and piazzas the 18th century is still a tangible presence, and director Lasse Halström and his cinematographer, Oliver Stapleton, have captured its glistening canals and its gorgeous, watery light with loving mastery. It's a movie you can almost swim in.

—Kurt Loder

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