ping-pong tennis, tonight. make sure to watch. [ laughter ] have a great afternoon, everybody. captioning sponsored by cbs o donnell: tonight, the big change is coming to congress as nancy pelosi, the first woman to be elected speaker of the house, announces she ll step aside. plus the history-making lawmaker who could succeed her. when i came to the congress in 1987, there were 12 democratic women. now there are over 90, and we want more. ( cheers and applause ) reporter: for years, the most powerful woman in washington. tonight, the end of an era. college murder mystery after four friends were brutally stabbed, what the coroner is saying about the knife. border agents attacked, a federal officer is killed in a shootout with suspected drug smugglers. frigid forecast, the treacherous