"Letters to the End of the World," a new play written and directed by Charles Dudley, and playing at the Studio Theatre at Theatre Row, under the auspices of the At Hand Theatre Company, through May 16, is set in New York City and in a village in Zambia in 1998 and '99. Its concerns are AIDS/HIV in America and AIDS/HIV in Africa and the differences and similarities that draw people together or drive people apart. Some of the play is epistolary and some of it is dialogue. There's an exchange as lyrical as a love song and one that's an actual song of mourning, of keening. Someone waxes mystical or intellectual, while someone else waxes melodramatic. Sometimes we wonder if they hear each other at all.

AIDS and HIV inspire diverse reactions and many are aired here. There's denial, even when death is a daily visitor, there's fear and there's anger and the desire to build a wall around oneself to avoid being hurt. There's idealism, the inclination to help, and the effort to be strong or the choice to withdraw. There are, inevitably, cultural clashes, but also class differences, that cause characters to lash out in frustration.

All of these are vividly probed by Charles Socarides and Peter O'Connor as Todd and Bryan, an American gay couple; Shannon Burkett portraying contrasting sisters, Agnatha Miller, an inspiring journalist, and flighty Tess; and, as Africans, running a combination school, clinic, and community center, Francesca Choy-Kee as Rebecca Mwando, a teacher, and Tyrone Mitchell Henderson as Emmanuel, charged with making coffins for the village.

Remaining performances are from Thursday to Saturday at 8 p.m. and Sunday at 7 p.m. For tickets, visit www.ticketcentral.com, telephone 212/247-4200, or go to the box office at Theatre Row at 410 West 42nd Street, between Ninth and Tenth Avenues.