I don't know that being in love is a form of psychosis, but being 21 definitely is. It's difficult to determine how much of the erratic behavior on display in The Hottest State, Ethan Hawke's adaptation of his own 1997 novel, is meant to be attributed to love, and how much to being 21, but at a certain point irritation (or hindsight) takes over and it hardly matters. Because once you make it past the point when a love affair can result in a personal paradigm shift (moving back home, dropping out), or 15 phone messages over the course of an hour, it's not really a place you want to visit. That's the main dilemma of Hawke's film: He telegraphs the self-serious, banal, delusional, pretentious aspects of being 21 and in love too well, without fully transforming them into something of substance. Turns out it's just as brutal as you've been forgetting to remember.

It's fun to watch William (Mark Webber) fall in love with Sara (Catalina Sandino Moreno, last seen in Fast Food Nation). Fun and a little scary: completely and instantly sodden, William is a ship without a rudder, just looking to drop anchor somewhere safe. We learn that safety is something of an issue for the lad, whose father Vince (played as an adult by Hawke) split when he was a kid and who now resides somewhere in Texas, the hottest state of the title. Meanwhile aspiring actor William hits the Williamsburg scene, where he has slept his way through his circle of friends (including an extra pouty Michelle Williams) and must turn to newcomers like Sara, a singer with a dream and an impressive rotation of peasant dresses.

Sara is skeptical of William's effusion -- he writes mushy notes and would rather watch her than the screen in a movie theatre -- and decides to make sex his proving ground. Or no sex. The first stages of their relationship (and particularly a long sequence in her new apartment) move through conversational exchanges like a series of tableaux, and indeed the couple are posing and stretching into different configurations, trying to see which one, or which version of themselves, will fit together. The ensuing clashes are bitter and boring, as full of back-biting and petty ego chipping as they ever were. They reminded me of the young couple who used to live below me, specifically the incredibly tedious, screeching shitshow that erupted early every Saturday morning, after a Friday night out -- "You left me alone for an hour!" "You were rude to my friends!!" -- and how glad I was when they finally broke up (oh, I heard the whole thing, believe me) and moved out.

Hawke's direction of these scenes is the most inspired thing about them; when the couple visit Sara's mother (played by Sonia Braga), a handheld camera moves in on the trio seated at a table, unsteady and tentative as it follows what shapes up to be a meet-the-single-parent dinner from hell. New York also looks nicely bedraggled, forever at that hour after night passes but before sunrise (oops!), when the streets are eerily tame and the light a dreamy, glowing gray.

Their trip to Mexico, during which Sara lifts the underpants embargo and mucho sex-o ensues, is not the revelation that is intended; it's very difficult to root for such a feckless duo. The reticent, benign Sara keeps asking William, "Why do you like me so much?" and I kept wondering the same thing. William is clearly a dreamer, an actor, but unable to assimilate what he is feeling in a remotely human way, erupting instead into violence. In his voiceover (Webber's voice has an uncanny similarity to Hawke's, in its resort to high, tremulous sputter) intersperses some hit and miss epigrams with as close as an answer to Sara's question as the film will get: she is not conventionally sexy, but she's funny, she's human, in a way that pierces him.

Laura Linney charges in as William's exasperated mom, and does some of the finest work in the film with the least amount of material. Some time is given to the idea that if you've been left at an early age, a loved one disappearing later on has the power to ruin you -- as it ruins William when his relationship falls apart. But not enough to imbue the delicate and moving reunion of William and his father with the impact it needs to reward us for an eternity of butt-numbing, break-up drudgery.

"It's so hard to miss someone who lives eight blocks away," William whines, during one of the umpteen phone calls met with Sara's icy, un-Latina reserve, and who can argue with that? Harder still, though, to miss someone who makes up 50 percent of your DNA, who essentially lives in your bones and is expelled in each breath. The Hottest State is certainly about a first heartbreak, but seems to arrive at its actual destination only after a muddled and taxing detour through heady, existential confusion and mass transference mixed in with a dash of genuine romantic duress. Ah, to not be 21 again!