MEDEA by Euripides; directed by Joy Zinoman; designed by Russell Metheny; costumes by Henry Shaffer; lighting by Greg Basdavanos; music by Robert Martin; with Nancy Paris, Danny Levine, Luke Christopher, Martin Goldsmith, Mikel Lambert, Edmond Mercier, Timothy Rice, Paul McCarren and Richard Hart.

At the Studio Theatre through Oct. 26.

What's this?A Greek tragedy without a rock accompaniment, without references to Napoleonic France or Weimar Germany or the Vietnam war, without anyone smoking a reefer or wearing a warm-up suit? A Greek tragedy with a bona fide classical chorus, with a constant awareness of the religious rituals from which these plays sprang, and set in, of all places, ancient Greece?

It was not want of imagination that led to these unexpected choices for Studio Theatre's production of "Media," but the company's commitment to doing plays in their original styles and settings, as far as resources allow. The resources include: a first-rate pair of actors for the leads, Mikel Lambert as Medea and Timothy rice as Jason; splendid costumes by Henry Shaffer (adorned with Elizabeth Stewart's enterprising jewelry); a great, brooding hulk of a set by Russell Metheny; and director Joy Zinoman's evenhanded attention to physical detail and dramatic substance.

Written in 431 B.C., Euripides' "Medea" was based on the legend of the Golden Fleece, which Jason had fetched from Colchis in Asia Minor in order to lay claim to the throne of his native Iolkas. Medea was the barbarian daughter of Colchis' king, who sided with Jason against her own people, then fled with him back to Iolkas and fought by his side in a bloody but unsuccessful effort to secure the crown he had been promised. Then they fled into exile in Corinth, under King Creon's protection, where Euripedes took up the tale.

"Medea" begins with the news that Jason, prompted by ambition and traditional Corinthian xenophobia, has decided to abandon Medea and marry Creon's daughter. So persuaded is he by his own peculiar notions of rational, civilized behavior that he tries to convince Medea that this marital realignment is in their mutual best interests. But she can't see the bigger picture. "You think that all is well as long as your life at night runs smoothly," Jason tells her (in David Damrosch's forceful, straightforward but sometimes rather prosaic new adaptation).

His wife replies that there is nothing worse than a "man who can make an evil thing sound plausible, and dares to do so" -- a line that generated widespread, mainly female applause at Sunday night's opening. Actually, Medea has not only failed to see the wisdom of Jason's arguments, but has decided on a terrible revenge -- the murder of his bride-to-be and of her own (and Jason's) two small sons.

This is a role of almost unmitigated rage, and it needs an actress of great dignity with a thunderous but subtle voice and the skill to show a great hurt even as she plots awful deeds. It needs an actress, in short, like Mickel Lambert.

In her stately robe, jeweled braids and sprawling necklace, Lambert looks like the last wife on earth you'd want to wrong. And she has a voice capable of dominating the action from offstage, deep in the bowels of designer Metheny's carpentry. But the supporting case is somehwhat bland and indistinguishable, if in a loud, energectic way. (Edmund Mercier does not cut a very kindly figure as Creon, for example -- but in his defense, it is hard to see how anyone could actually act inside a costume that makes him look like a giant, wind-up armadillo.)

But the mistakes and slow spots are overwhelmingly outweighed by the grandeur and authority of this production, which marks another impressive step forward and upward for the Studio Theatre.