It's hard to separate fact from fiction in this series about Washington, D.C., political operators. And I'm not sure it's worth the effort. George Clooney and movie director Steven Soderbergh are among the executive producers behind K Street's tricky concept. A fictional consulting firm, staffed by made-up characters (portrayed by John Slattery, Mary McCormack and Roger Guenveur Smith) as well as real-life Beltway insiders (James Carville and Mary Matalin, playing themselves), handles timely issues involving actual politicians, who appear in cameos. The improvisational acting can be painfully awkward, particularly when amateur Carville drags professional Slattery down with him, and the topical talk too often lacks coherence. Even political junkies may be glad it's only a half-hour show.