In a local diner in a small unnamed town, a waitress and a regular develop a friendship. The everyday routine is part of the charm of their relationship, with conversations unfolding in the brief moments it takes to pour a cup of coffee. Everything shifts when the regular disrupts the routine by requesting a shocking favor, which in turn brings deep secrets to the surface. Meghan Kennedy’s new play, funny and moving, reminds us how life can change in an instant. It’s directed by David Cromer, who won a 2018 Tony Award for The Band’s Visit. —Jeanne Malle