Dublin, 1907. A young actress begins an affair with a damaged older man, the leading playwright at the theatre where she works. Outspoken and flirtatious, Molly Allgood is a Catholic girl from the slums of Dublin, dreaming of stardom in America. Her lover, John Synge, is a troubled genius, whose life is hampered by convention and by the austere and God-fearing mother with whom he lives. Their affair, sternly opposed by friends and family, is quarrelsome, affectionate and tender.

Many years later, Molly, now a poverty-stricken old woman, makes her way through London's bomb-scarred city streets, alone but for a snowdrift of memories. Her once dazzling career has faded but her unquenchable passion for life has kept her afloat.