A Diet to Die For — Joan Hess

Thanks to her deplorable weakness for saying yes when she should say no, Claire Malloy finds herself escorting Maribeth, an overweight, depressed heiress, to her diet and fitness sessions. But while the arduous regime is taking off pounds, it also seems to be addling Maribeth's brain--a development Claire attributes to something other than the torture of aerobics, a nine-hundred-calorie diet, and her rotten home life. It appears that Maribeth isn't quite her own worst enemy--someone else has that deadly distinction.

But can Claire, who is deeply opposed to sweat on principle, survive a forty-minute workout to learn the truth?