Bill had planned everything out very carefully,” I explained. “He told John Costello to call Sarah on the phone to ask her for some help with his computer. When she got there, John tied her up and kept her in his room. Bill left Los Angeles for two days in a rented car, so people would think both he and Sarah had disappeared. And it worked: Anne called the police, because she thought that both Bill and Sarah were in trouble. That’s when Anne asked me for help.” “What went wrong with Bill’s perfect plan, then?” “The problem was that John Costello wasn’t a very good helper,” I said. “He was supposed to kill Anne on the freeway, but he didn’t. Then he told Bill that if Bill didn’t give him more money, he would tell the police about the kidnapping.” “That’s when Bill decided to kill Costello, to make sure Costello didn’t tell the police?”