''Anna's missing, Anna's sick, Anna's gone off her meds.'' Daisy Hubbard has heard those words about her sister many times, but this time, it seems, there might be cause for concern. Summoned by an alarmed detective from the LAPD, Daisy, a scientist, takes a leave from the prestigious Boston lab where she's studying a deadly neurological disease and flies to Los Angeles. Tracking a schizophrenic, it turns out, is no easy task, especially when Daisy and the detective, Jack Makowski, realize that Anna's disappearance may be the work of a serial killer and that Daisy's own medical research may be involved. What begins like a boilerplate thriller in Alice Blanchard's Life Sentences soon takes dozens of swift twists before a completely unexpected and satisfying resolution.