In An Iliad by Lisa Peterson and Denis O'Hare, a weary man carrying an old suitcase and speaking ancient Greek comes onstage. No wonder he's exhausted: He's travelled 3,000 years to sing his song again.

This solo play revives the ancient oral tradition as this latter-day Homer, played heroically by Peter DeLaurier, recounts once again the story of the war between Greece and Troy.

An Iliad is nearly two hours of impassioned speech, performed with few props, requiring a virtuoso actor who can convincingly shift between characters, from the Poet to the desolate Andromache, to the feckless Paris, to the "shining" Hector, to the proud Achilles, to Helen ("bitch that I am, vicious, scheming"). I wish DeLaurier had altered his voice more for each character, but the only real difference is an odd accent and rhythmic delivery that I imagine is supposed to sound "classical." The play seems to me to depend on the overlay of a contemporary and often ironic voice, and that was often missing here.

The Homeric devices of repetition and incantation are part of the enthralling power of this play, but most powerful is Homeric list-making. It is most devastating as the Poet begins a list of wars, beginning with the Peloponnesian War, continuing through the Crusades, Hiroshima, Vietnam, Sarajevo, and stopping - probably, sadly, only for the moment - with Syria. The list is four pages long. Single-spaced. As the Poet sadly tells us, "Every time I sing this song, I hope it's the last time." And that's the point.

Homer's epic glories in the glories of war - the 10 years of mayhem and stalemate that was the Trojan War, which destroyed an elegant civilization and razed the "topless towers" of a great city. The list of great cities destroyed by war since Troy ends in my copy of the 2010 script with Kabul; now the list ends with Aleppo. As the Poet says to us, "You see?" And of course, we do: An Iliad is a moving and persuasive anti-war play.

Director M. Craig Getting has made some decisions that altered the effect of the show for me. First, he added a muse - not the idea of a muse (inspiration) but a flesh and blood Calliope (the muse of poetry). She is played by Liz Filios, who never speaks but plays various instruments, sometimes distractingly. The other choice was to have DeLaurier, confined by a cluttered stage that is small to begin with, limit himself to a few repeated gestures.

But these are quibbles; there is no denying the enormous effort this performance requires, and DeLaurier's Homer holds us rapt in his story until he releases us at the end. An epic is a long narrative poem that recounts heroic deeds and events that are significant to a nation or a culture. Performing this play is itself the heroic deed, with plenty of significance to our nation and culture.

An Iliad. Through Dec. 11 at the Lantern Theater, 10th & Ludlow Sts. Information: 215-829-0395 or lanterntheater.org.