"The tourism of atrocity."

Is going to see the sites of historical horrors — Nazi concentration camps, Pol Pot's killing fields — a moral responsibility or a vile indulgence? How about revisiting them? Consider Rwanda. We learn in Sean Christopher Lewis' compelling Dogs of Rwanda, being performed at the InterAct Theatre Company through June 18, that in Rwanda there is an old woman who shows tourists around in exchange for a few coins. She is a survivor of the 100-day 1994 genocide — called "the Bad Time"— when the Hutu ethnic majority slaughtered 800,000 members of the Tutsi minority.

And then there are those who come back to the scene of atrocities they once saw. David, a dog-lover and writer, has received a note about a book he wrote: "There are untruths here." The book is an account of his experience 20 years before, as a 16-year-old missionary in Africa, when he and his girlfriend, Mary, literally stumbled into the genocide. As bodies floated down the river, a young man named God's Blessing leads them into the woods. He is the author of the note.

This play is a fascinating and exhausting hourlong monologue, performed with great power and subtlety by Dan Hodge. The gruesome details and the action-filled chronicle are riveting — an enormous challenge in a solo show. Past and present weave together in this account of an episode so harrowing that David will never recover from it, no matter how many books he writes and how earnestly he wants to honor God's Blessing as the hero of his youth. Dogs of Rwanda offers no easy moral lessons, only psychological traumas and philosophical meditations on the evil in the world. It is, the play shows us, hard to find forgiveness. It is, it shows us, worse to be left unjudged than judged.

Hodge, master of the sickly smile, never simplifies or illustrates; this is acting that refuses to be seen as acting. Directed by Maura Krause, the show is shaped on a small strip of stage in front of the set for InterAct's How to Use a Knife — a terrific concurrent production I highly recommend. That play is only obliquely about "the thing," as the Rwandan genocide is called there, yet its role there is of moment. The two shows are most interesting when seen in tandem, both politically and theatrically.

Lewis' Dogs of Rwanda is filled with small motivic links that knit the play together, far more complex effects than I could catch in one viewing. I kept hearing Shakespeare's terrifying lines from Julius Caesar roar around in my mind:

Cry "Havoc!" and let slip the dogs of war,
That this foul deed shall smell above the earth
With carrion men, groaning for burial.

Not the same dogs, of course, but "Havoc" just the same.

Dogs of Rwanda. Through June 18 (Saturdays, Sundays, and Mondays only) at the InterAct Theatre Company at the Drake Theatre, 302 S. Hicks St. Tickets: $20  Information: 215-568-8079 or interacttheatre.org.