"Jo is called to the scene of an aircraft inbound from London to help deal with a passenger who is behaving erratically. She figures out that he's got anteretrograde amnesia, and can't form new memories. As his thoughts drift away like tendrils of smoke, Jo finds herself racing to save a patient who can walk and talk yet can't help her figure out just what happened to him. For every cryptic clue he is able to drag up from his memory, Jo has to sift through a dozen nonsensical statements. Suddenly a string of clues arises - something to do with a superdeadly biological agent code-named "Slick," missing people, and a secret partnership gone horribly wrong. Jo realizes her patient's addled mind may hold the key to preventing something terrible from happening in her beloved San Francisco.