To find Masu, downtown's newest Japanese restaurant, you must notice a modest sign on the door of a commercial building, tucked just around the corner of the flashy American Apparel store on Southwest Stark Street, and then make your way up a dim stairway.

Once you step inside, though, the restaurant's interior beguiles with its sexy urbanism: low, modular sofas and undulating bent-plywood chairs; industrial windows with ripply leaded panes that refract the streetlights; walls and columns clad in cleverly layered wood chips, and a central bar gleaming with lit glass. The focal point of the space is a massive backlit grid of shelves behind the sushi bar, displaying dozens and dozens of masu.

Masu are the little wooden boxes that Japanese sake brewmasters traditionally used to sample their ware. Made from fragrant hinoki cypress wood and constructed with neat dovetail joinery, the masu is an impeccable object with a task both delicious and deeply sacred. Portland's new restaurant seems aptly titled: This chic little boîte has taken it upon itself to bring grace, premium sake and, most daringly, civilized Japanese food to downtown. What Masu serves, along with its refinement, is in-the-know urban cool.

The menu offers a compromise between Western-style platings, the typical à la carte sushi experience, and a love affair with tempura. A page devoted to specialty sushi rolls displays the kitchen's muscular style: One standout is the Japanista, a juggernaut of spicy crab, tuna, seared yellowtail, sprouts, cilantro and jalapeño. Delivering enormous pieces, it's almost an entree—and at $13, it should be. Like many of Masu's sushi and entrees, it's served with sauces—here, little dishes of sweet chili and the house's citrus-and-mayo Hana concoction.

Masu's sauces kick its food out of the realm of simple raw fish and into a heavier, more formal kind of dining, as does the inclusion of fried rolls—the best of which is the Bamboo Princess, a showy mix of scallops, crab and shrimp in tempura-fried soy paper ($9). Masu does offer the standard check-'em-off broad for those seeking simpler fare, but it's not the best value (a spicy tuna roll, for example, costs $7).

The appetizers are a playful blend of traditional Japanese ingredients and artsy prep. The spicy calamari salad ($5) is served as a tumble of chili-spiced squid pieces in a rice bowl with garlic ponzu sauce. A delicious halibut carpaccio ($9) offers thin slices of tangy cured halibut fanned on a plate with shiso mist and torn greens. The kaiso appetizer ($4) tinkers little with the traditional wakame salad (though the menu notes that the seaweed is organic).

Masu's cocktails offer the best realization of the restaurant's urbane ambitions. The bar has a knack for burying alcohol's bitter edge in fragrant herbs and exotic fruit, so a stiff drink feels like a healthy adventure. The Asterix Gimlet ($7), which mixes gin with fresh kiwi, lime and a housemade lemongrass ginger soda, tastes like wet springtime, served tall. The Tokyo Drop ($7) renders vodka undetectable in a mist of muddled red grapes, lime and lychee. The Masu Mojito ($8) is spiked with Coco Rico coconut soda and pineapple.

Entrees, which range from a straightforward vegetable-and-tofu yakisoba ($17) to an elaborate wild-salmon confit with leeks and beluga caviar ($19), don't achieve the elegance that the space (or the price tag) demands. The confit is really a simple filet, dotted with beads of salty caviar, long on flair but without the kind of delicacy that earns a kitchen extra praise. The blackened rib-eye steak ($21) was still more uneven—a rib-eye, sharing an oblong plate with daubs of applesauce (poetically described as "Asian pear and Fuji apple relish") arrived rare at one end and well-done at the other.

It's not clear why Masu needs these big-ticket items—it would seem more natural to let the sushi bar (and the bar) take center stage. Similarly, desserts (including a dense chocolate-Chambord cake and ginger crème brûlée, all $5) are decent but taste as if they were trucked in from another kitchen.

What's more, the restaurant's fine-dining feel is at odds with the service, which can be casual to the point of disappointing. A server, when asked for sushi recommendations, might say: "That's a good one," to every specialty roll on the menu. There can be inexplicably long waits between ordering and the time when drinks or food actually arrive at your table. And the staff doesn't seem that knowledgeable about the more exotic items on the menu—notably the premium sakes, which run as high as $291 a bottle. Try the Oni Koroshi, by the way—it's called "demon killer" for a reason.

Masu's instincts are definitely good, and its confident presentation makes the place a welcome bright spot in downtown's sometimes dreary dining landscape. The kitchen serves an abbreviated menu (mostly sushi and appetizers) until midnight every night of the week. Throw in the delicious cocktails, and those pluses are more than enough to make Masu a must-visit.

All that's needed here is a tightening up of the concept and a sanding down of some rough edges. Think of the masu box itself—simple, designed exactly to its purpose, perfect in its simplicity. If the restaurant can, without distraction, master late-night maki rolls and a mojito, this Masu can achieve perfection, too.


406 SW 13th Ave., 221-6278.11:30 am-2 pm Monday-Saturday, 4 pm-midnight Sunday-Thursday, 4 pm-2 am Friday-Saturday. Credit cards accepted. $$

Picks: Japanista roll, Bamboo Princess fried roll, spicy calamari salad, Asterix Gimlet, Masu Mojito