Sometimes "Screenplay," by Istvan Orkeny, seems more a thing to be studied than to be watched. The last play of a modern Hungarian master, it twists and turns with its own relentless logic, even as it makes a mockery of time and truth. In other words, it's not very entertaining -- but it sure gives you a lot to think about.

The Arena Stage's production, directed by Zelda Fichandler, has its share of rewards for the folks who can stick it out. There's craftsmanlike acting, especially by Stanley Anderson as the lead, on an inventive set by Karl Eigsti, evocative music and sound- effects, and well-designed lighting and costumes. If the proceedings at times reach tedium, they also approach technical perfection.

The play is set at the Great Circus of Budapest, circa 1949. Or rather, it centers on the show trials -- aka "Screenplay Trials" -- of that year. Or perhaps the Hungarian Revolution of 1956. No. Instead, it's wartime, and 1944. Actually, it's all four, with the protagonist, one aptly named Adam Barabas, as unstuck in time as Billy Pilgrim ever was.

As the years go back and forth like a bumper car, Barabas -- in the sway of a ringmaster/hypnotist and a few select comrades -- reveals himself variously to be hero and coward, patriot and traitor, freedom fighter and Nazi collaborator, cynic and idealist -- and a goulash of other contradictions.

Loosely based on the 1949 show trial of Hungarian foreign minister Laszlo Rajk -- some brushing-up beforehand certainly wouldn't hurt, and being Hungarian would probably help -- "Screenplay" works in the half-light of dreams, and in the garish bursts of nightmares. The set -- a circus ring with ladders, pulleys, trapezes, crododile, gorilla and bear suspended above it -- enhances the script's heaviness: its sense of Slavic doom.

It heaves with Okrney's observations. "This country belongs to the eavesdroppers, the informers," says one of his characters, who, like the others, seems less human than symbolic. "The ones who send the innocent to prison. . . My son reported me for stargazing. I was a stargazer and therefore a counterrevolutionary."

Another character, Misi the Clown, has even better things to say: "I told you art was unpredictable." SCREENPLAY -- At the Arena through March 13.