AH, TO THINK BACK UPON those glorious salad days, long before Meet the Fockers and Legally Blonde 2, back when Owen and Luke Wilson held such vast promise. They made their debut in the 1996 indie Bottle Rocket, a comic caper co-written by Owen with his University of Texas classmate, director Wes Anderson. That movie was a disarming mixture of nagging comedy and unabashed bigheartedness, and it announced the Dallas-born Wilsons (Owen in 1968, Luke in 1971) as two intriguing variations on a slacker theme. Owen was the garrulous, restless self-improver, the guy with big plans and limited follow-through. Luke was the more soulful introvert, the doe-eyed dreamer whose hopefulness so often curdled into disappointment. (The best line in the movie: Luke’s character complaining to Owen’s, “Your seventy-five-year plan does not seem to be working.”)

The promise only kept expanding, and for a brief moment our native sons seemed poised to replace the Bridgeses, Quaids, and Dillons as Hollywood’s most exalted brother duo. The two screenplays Owen next co-wrote with Anderson, Rushmore and The Royal Tenenbaums, proved uncommonly ambitious—glib comedies that, in small but steady measure, also reveal a surprising emotional reach. And Luke delivered a pair of neatly understated performances—in the terrific screwball Home Fries, opposite Drew Barrymore, and in My Dog Skip, playing a haunted war veteran—that hinted at a serious actor in the making.

Except both Wilsons seem to have drawn all the wrong lessons from their early successes. While he was working with Anderson, Owen began appearing in big-budget productions like Armageddon and Meet the Parents. With his pothead patois and his surfer-boy mop of hair, his very presence in these movies seemed an ironic commentary on the state of contemporary blockbuster moviemaking (only in Hollywood could someone this relentlessly goofy be passed off as a geologist who saves the world). Owen was crafty enough to let us in on the joke and to keep one eye winking at the audience, but his hipster detachment quickly calcified into a trademark. For nearly five years now, he’s given almost exactly the same performance, playing the perennial class clown who’s forever too cool for school. For those same five years, he’s turned up in almost nothing but sidekick roles in buddy comedies; in true slacker fashion, he’s all too willing to let the other guy (usually Ben Stiller) carry the show. His repetitiveness has made it virtually impossible for him to make the shift into dramas (see the laughable Behind Enemy Lines). Even in a raucous comedy like Wedding Crashers, he leaves an emotional hole in the center; we never really believe that his shallow character could actually fall in love with one of his wedding reception conquests. (That, and he stands contentedly to the side as Vince Vaughn hijacks the movie entirely.)

As for Luke, his career arc has been even more disappointing, perhaps because he seems to have spent the past few years chasing after Owen’s box-office success. He gave the most deeply felt performance in The Royal Tenenbaums, playing a tennis prodigy with suicidal tendencies; unlike his brother, bald-faced emotion suits Luke well. He might have followed the path of someone like Dustin Hoffman or, more recently, Edward Norton and fashioned himself a tortured American everyman for these uncertain times. But instead he opted for parts that required him to stand around and look harmless. Like Owen, Luke has turned into his own type: the vanilla leading man who causes no distraction. His latest achievements: playing Cameron Diaz’s nice-guy boyfriend (in the Charlie’s Angels movies), playing Reese Witherspoon’s nice-guy boyfriend (in the Legally Blonde movies), and playing the nice guy who is easily flummoxed as Kate Hudson acts wacky (in the excruciating Alex and Emma). His one attempt to step outside the Hollywood box—the still-unreleased comedy-drama The Wendell Baker Story, which he wrote and co-directed with his older brother Andrew (and which features Owen in a supporting part)—strains too hard to rekindle the magic of Bottle Rocket. His touching work in The Family Stone notwithstanding (see “Worth the $2.99 Rental Fee”) he now seems perilously in danger of becoming his generation’s Mark Harmon.

It’s time the Wilsons cast off their twentysomething slacker affectations and start acting like, well, real actors. Luke, we can hardly begrudge your cashing an easy paycheck for Hoot, the Encyclopedia Brown—ish mystery-comedy for kids opening this month. But start turning away from romantic comedies like this summer’s My Super Ex-Girlfriend, co-starring Uma Thurman, and get thee to the indie leagues. You might even want to think about playing against your boy-next-door good looks—and finding a bad-boy role that doesn’t require you to be so freakin’ nice.

And Owen, a few gentle pleas: Stop hanging with Ben Stiller, lest you commit another sin like Zoolander or Starsky and Hutch; forget about the Hollywood comedies where you play the funny stoner dude (like You, Me and Dupree, opening in July); stop providing your irony-soaked voice to the likes of Pixar’s animated Cars (opening in June). Instead, plant yourself in front of a typewriter, preferably one located directly across from your old pal Wes Anderson. If the dreadful The Life Aquatic With Steve Zissou (the first Anderson movie written without you) is any indication, he needs you almost as much as you need him.

Worth the $2.99 Rental Fee: The Performances They Got Right
In last winter’s The Family Stone  (available on DVD May 2), Luke plays the lovable underachiever forever toiling in the shadow of his financially successful older brother (Dermot Mulroney). A case of life bleeding into art? Perhaps. But instead of seeming uptight and slightly petulant, as he often does as leading man, Luke sends off relaxed good vibes every pot-addled step of the way. And in the marvelously underplayed scene where Diane Keaton lets him know she’s dying, he captures a son’s love for his mother with straight-to-the-heart acuity. On the other hand, you won’t need any handkerchiefs for Shanghai Noon and Shanghai Knights, two underrated action comedies in which Owen plays hilariously off Jackie Chan. They are the rare mismatched buddy team between whom genuine goodwill seems to be blossoming. And for once, Owen’s snarky shtick—anachronistically recast in the Old West (in Noon) and in London circa 1887 (in Knights)—is very witty.

Christopher Kelly is the film critic for the Fort Worth Star-Telegram.