Happiness comes only in moments. And to ensure those moments, sometimes drastic action is necessary. Closing out their 2016/2017 mainstage season, the Maryland Ensemble Theatre brings to the stage a rarely produced darkly-driven British comedy. Fred’s Diner, by Penelope Skinner, takes place in an American 1950’s themed diner in present-day Britain just off the major motorway. Everything looks hunky-dory, as the Yanks might say, but upon closer examination, things aren’t always what they seem.