The Blue Moon Studio Theater makes a sparkling debut with George Howe and Frances Limoncelli’s new one-act musical, based on Eileen Spinelli’s children’s book about the “constantly friend-resistant” Mr. Hatch. His dour demeanor changes, however, when he gets a valentine from a secret admirer. Bradley Bartolo’s clever bare-bones staging racks up one delight after another; the four actors are in delicious sync and they give the lyrics panache, really selling the wordplay. As Hatch, Evan Sierminski is the perfect blend of wallflower and curmudgeon, Lindsay Naas is a saucy gem as a desperate housewife, and Leah Morrow and Marcus Fittanto are talented physical comedians. Though the story’s set in February, this is a toothsome late-summer treat–sweet, but not too sugary–and easily enjoyed by all ages. Through 9/3: Fri-Sat 8 PM, Sun 7 PM, No Exit Cafe, 6970 N. Glenwood, 312-802-0054, $5-$12.