Matthew has an intermittent series of treatises on the virtues of the Big Three trilogy movies... Star Wars, Lord of the Rings, and the Matrix. (I know I know, one of these things is not like the other...)

I want to add a category to the debate:
Best Use of Hair in a Trilogy.

The Matrix movies use hair to good, albeit subtle, effect. You can tell whether Neo is in The Real World or The Matrix based on whether he has the buzz cut or not. You also have bald Morpheus, which means he can wipe the floor with your wussy self. In movie parlance, bald=badass. Hair is not just an aesthetic issue here, but is integral to and supportive of the plot.

As for Star Wars, but of course! Leia is not merely the Princess, but the Queen, of movie hair. The double buns! The ceremonial updo at the end of Ep IV! The double doggie-ear braids in Cloud City! The cascading curls in Ewok Village! It's a cavalcade of coiffure!

Unfortunately, Star Wars is out of the running because the rest of the hairstyles hopelessly date the film [coughLukeandHancough]. Admit it. You love the series, but the first film in particular is hopelessly ensconced in the 1970s, and it's not the quaint special effects so much as the bad Luke Skywalker lid.

No, Best Use of Hair in a trilogy goes to Lord of the Rings, hands and hairdryers down. Of course, the Legolas/Aragorn dichotomy is obvious. There's the former, with his luxurious blond locks that are never out of place, no matter the skirmish--an appropriate 'do for an elf, no? You can practically smell the jojoba. Then there's the latter, with his greasy tangled mess, befitting a grungy Ranger. Honestly, Viggo in this film is a graduate of the Ethan Hawke School of Grooming. (And yet, we [heart] them both. Don't we ladies?)

But those are just hair styles. Big deal. No, LOTR gets the award for its groundbreaking use of Hair Acting. Yes, Peter Jackson manages to coax actual performances from the hair itself. He's just that good.

Don't believe me? Check out King Theoden's hair, particularly in blustery Edoras. It swirls majestically about his face, particularly during climactic moments of great decision. Even Aragorn's grease-do rises to the occasion, swinging heroically as he throws open the doors to inform Theoden of impending doom. The Uruk-hai are coming! The Uruk-hai are coming! Each strand shrieks a warning.

Eowyn's hair gives a more understated performance, but also roils about with a great romantic intensity the likes of which I have not seen since the workmanlike performance of Princess Buttercup's golden tresses.

No contest. LOTR sweeps the Academy Awards.

Vidal Sassoon Academy, that is.