Michael Landrum, the meat maverick who turned the modestly appointed Ray’s the Steaks into the area’s most rewarding steakhouse, is taking on a new genre: seafood. Ray’s the Steaks will vacate its tiny Arlington storefront (1725 Wilson Blvd.; 703-841-7297) next year for larger space up the street, and Landrum will convert the restaurant into Ray’s the Net. The goal, he says, is to present seafood and fish as simply, freshly, and cheaply as possible. “You’d never guess the insane markups fish and seafood have,” he says. The question: Will the new restaurant inspire the same allegiance as its predecessor, which was so busy on a recent weeknight that would-be diners—Ray’s doesn’t take reservations—were milling in front, sipping free red wine?