A second case for 60-ish San Francisco lawyer Dade Cooley (Murder Mystery)--which starts with a call for help from client Kate Mulvaney, an eccentric, miserly millionairess vaguely in show-biz, now vacationing with her family on a barge-trip in France. But Cooley and wife Ellen arrive just in time to see Kate's body being pulled from the canal--so Cooley is soon helping Inspector Marbeau as translator/sidekick. Among the familial suspects: philandering husband George; actress-sister Maggie, whose writer-husband Dan has just been cut out of Kate's newest movie project; Dan's sister Cissy, engaged (in name only) to Kate's nephew/business advisor Billy; plus Kate's brother and his actress-wife Olivia. All of these folks snarl at each other while Cooley travels the countryside, trying to reconstruct Kate's last days--which centered on her obsession with a supposed medieval ancestor (the Bishop of Remords) and a priceless stolen reliquary cross (which Kate was determined to return to its cathedral). Was this the murder-motive source? Or was it the nasty scams among the batty relatives? Cooley eventually sorts it all out, two deaths later, trapping the murderer via a corny blackmail bluff. But though the old French towns are described with warmth and flair, this is, like Murder Mystery, lumpy, bumpy going--with an overstuffed plot, aimless details, and shrill, unpleasant characters galore.