The press reported the drowning of Professor Alex Shugar as a case of accidental death. And Shugar was well known among her friends for taking chances, personally and professionally. So, this all seemed-at least to most people-to be just what happens when a risky solo swim goes wrong. Certainly Maddy Shanks, with her brand new PhD, has no reason to think, when she is asked to take over Shugar's courses in Minneapolis, that there's anything suspicious...