Enacted by the delightful, gifted quartet of Michelle Blocker-Rosebrough, Melissa Anderson Clark, Sheri Olsen, and Erin Platt, The Marvelous Wonderettes is Countryside Community Theatre’s intentionally minimalist summertime offering after numerous seasons of grandly scaled, extravagantly cast Broadway hits. As it’s better to go small than go bust, I admire the organization’s decision to downsize. Yet if you know nothing about this undemanding musical, I urge you, in the interest of your time, to avoid the synopsis on its Wikipedia page, which details in 1,576 words what can be effectively distilled to 15: "Four young women sing ’50s songs at their prom, then ’60s songs at their reunion."