ONE FLEA SPARE, GreyZelda Theatre Group, at Stage Left Theatre. The year is 1665, and a prosperous London couple are confined to their comfortable home after their servants have succumbed to the black plague. Then they’re joined by two intruders, a neighbor child and an itinerant sailor. Their quarantine, interrupted only by the rumors that penetrate the boarded-up doors and windows, fosters a microcosmic social revolution, precipitated by shared confidences of excruciating intimacy.

The intimacy in this debut production is all the more intense because the GreyZelda Theatre Group is performing on the apron of a stage in a space that’s already snug (and underheated), barely arm’s length from the audience. Played too broadly, the enigmatic relationships in Naomi Wallace’s 1995 Pinteresque exercise could easily become as excessive and sensational as the play’s long-ago health crisis. Under Rebecca Zellar’s direction, however, the five actors never crowd the audience, physically or psychologically, instead focusing on the shifting dynamics between their characters and letting us draw our own conclusions about Wallace’s meanings. Rooting character revelation and plot progression in the smallest of actions might slow the pace somewhat, but the results are spellbinding.