LOST - "Enter 77" - Locke, Sayid and Kate investigate a strange structure and its mysterious inhabitant. Meanwhile, Sawyer competes in a ping-pong competition to get back his belongings, on "Lost," WEDNESDAY, MARCH 7 (10:00-11:00 p.m., ET), on the ABC Television Network. (ABC/MARIO PEREZ) NAVEEN ANDREWS, MIRA FURLAN, ANDREW DIVOFF, TERRY O'QUINN