One casualty of gay relationships is often the memory of past lives and loves, because until recently such relationships tended to lack offspring. Except to fine-arts scholars, for example, the name Monroe Wheeler — a transformative figure at the Museum of Modern Art — likely doesn't register today in the public consciousness. Nor will writer Glenway Wescott, Wheeler's companion for more than 60 years; nor will photographer George Platt Lynes, Wheeler's other companion during 15 of those years.

Fortunately, their correspondence, journals, and other biographical materials are extant, and Joe Salvatore, an actor, playwright, and director, has used them to fashion the profoundly moving III, which anatomizes this most endearing and enduring of ménages.

There are times early on when one might ask Salvatore to rely less heavily on primary source materials and to be even more daring in his dramatizations of events in the lives of these men. As a teacher in the Program in Educational Theatre at New York University, perhaps he's tempted to err on the side of pure instruction. But Salvatore's prowess at pure dramatic construction serves him equally well, especially as he charts the salient moments when Wheeler, Wescott, and Lynes cohabitated together on East 89th Street.

The actors — Salvatore as Wescott, John Del Vecchio as Wheeler, and Daryl Embry as Lynes — beautifully calibrate the curving, winding shape of their unlikely romantic and emotional bonds. Physically, psychically, and otherwise, their chemistry is extraordinary. They are — like the notable men they play — a fabulous trio for the ages.

Presented by Joes & Co. as part of the New York International Fringe Festival at the Cherry Lane Theatre, 38 Commerce St., NYC. Aug. 13-23. Remaining performances: Wed., Aug. 20, 4:15 p.m.; Sat., Aug. 23, 7 p.m. (212) 279-4488 or (866) 468-7619 or www.fringenyc.org.