What kills me about Opal is that it's not necessarily a bad restaurant; it's just so much less of a great restaurant than it once was. When I started this job four years ago -- when chef Duy Pham was making his first passing glances at genius in its kitchen -- Opal was my favorite restaurant in the city. It was beautiful, well-staffed and nicely balanced between sushi-and-sake nouvelle Japanese and solidly modern French. I once had a single dinner there with two friends that ended with a bill topping $400. And I was happy to pay it, because I knew I'd just finished one of those meals that I'd remember for years to come. Today, though, with owner Jay Chadrom scrambling to get his new venture, Aqua, open (see Bite Me) and better than three years of hit-or-miss operation behind it, the bloom is definitely off Opal's rose. The bar/lounge in the back still does a bang-up business among the young professionals in the neighborhood, but the dining room's silvery-gray and faded-purple decor is starting to look tired, and the menu comes in just this side of strip-mall Chinese. I had some very good mu shu beef, folded in rice-flour pancakes, and skipped the misspelled "low mein" in favor of kung pao shrimp that would have been better -- and cheaper -- at my neighborhood Little Super Panda Dragon Jade Mandarin Express. The vegetarian sushi was a nightmare of undercooked squash and carrots and too-loose nori; the quote/unquote Chilean sea bass tasted like fish sticks drizzled in honey and mounted over a pile of mashed potatoes. It's sad to see any restaurant stumble this way, but it happens -- more often than not. And now, my hope is that all the genius that once suffused Opal is being moved across the street to Aqua.