The formula that didn't click for Lexau in her first Miss Happ mystery, The Poison Ivy Case (1984), looks much more promising here. WiLy Nilly, suspected of strewing dog food through the house when he took care of Mr. Spring's Mutt, finds the same thing happening a second time--so he hies himself to problem-solver Miss Happ. That fluttery personage, a tiresome nit-wit on first meeting, has some better lines this time (""Does this water look sick to you?""/""Then it's well water"") as she goes about making magic that inevitably misfires. . . and accidentally solves the mystery. The source of the scattered dog food is, as you might sensibly suspect, a mouse. What you wouldn't suspect is that Miss Happ is really a softie: she suspects an elf--her elf, whom WiLy Nilly shouldn't tell Mr. Spring about, lest Mr. S. try to catch it. Pleasant whimsy.