Two years after John Neville-Andrews took over its artistic leadership, the Folger Theatre is a new place. Without going trendy, it has become responsibly adventurous. The taste and intelligence of its offerings have steadily risen from production to production. It was always a theater of great ambitions, but now those ambitions no longer seem to be pie-in-the-sky reveries. The Folger fairly writhes with possibilities these days.

By way of example, consider "All's Well That Ends Well," which opened last night for a run through June 19. Chic, disciplined, sure of itself--but not cocksure--the production takes one of Shakespeare's knottier plays and untangles it in such a fashion that it not only makes sense, but also makes for a definite fascination.

On purely visual terms, the evening is a knockout. Neville-Andrews has advanced the action to the early 19th century and most of the men sport trim military uniforms, while the women, under the thrall of Romanticism, are wearing elegant, long gowns, capped with extravagant bonnets. Costumer Bary Allen Odom has limited his palette to black and white, with the occasional gold epaulet, red sash or flashing ruby ring providing stunning accents. Against the bleached white sandstone set designed by Lewis Folden, the finery looks very fine, indeed.

Although basically geometric, Folden's design is far more astute than it initially appears. By raising and lowering several rectangular panels that stretch the width of the stage, the set alternately suggests a gymnasium, various kingly courts or the night forest. But it also has the purity of a Mondrian canvas on the move. Rarely has the Folger's playing space been used with such telling simplicity.

Simplicity is, in fact, the evening's byword. Neville-Andrews, who has directed the production, has refused to be ensnared by a plot that has long seemed an improbable tangle of love spurned, rings and things, disguise and duplicity--all of which is unraveled in a protracted denouement that taxes logic as much as it does patience. The sweetly intrepid but low-born Helena (Gwendolyn Lewis) has cured the king of a nasty malady. As her recompense, she asks to be married to Bertram (Peter Webster), a hot-headed French nobleman, who would rather carouse with his cronies. The marriage ceremony is barely over before Bertram has slipped away to the Italian wars, encouraged in his heelish ways by one Captain Parolles (Floyd King), a spineless creature of unlimited braggadocio.

Boccacio was Shakespeare's source, which gives you a hint of the convoluted means that Helena has to employ to reclaim her rightful husband and induce in him a just penance. The very sobriety of the Folger production, however, chastens the extravagance of the script, and if the plot is something of a goose chase, the actors are steering as direct a route as possible through its complexities.

It may be impossible to make Bertram wholly likable, but Webster has the romantic profile that turns maidens' heads and the kind of recklessness that, in our day at least, gets rock stars their groupies. Lewis brings primarily a pale, fine-featured beauty to Helena. Her acting benefits neither from a certain sibilance in her speech nor her stridency in moments of high emotion, but it can't be denied that she and Webster look smashing side by side. If only for esthetic reasons, you will find yourself rooting for their eventual reunion.

It is in the supporting roles that this production can lay its claim to finesse: Mikel Lambert, Bertram's fretful mother, lamenting her son's headstrong ways, but never losing her essential dignity; Vivienne Shub, a shrewd widow, thriving on the excitement of military men in town; and Gail Arias, who serves as virginal bait in the trap that will eventually catch Bertram. Arias manages to be both alluringly chaste and irresistibly flirtatious at the same time.

Thomas Schall and Craig Paul Wroe play two brothers in arms with a refreshing lack of the usual stomp and gusto, and John Wylie, as General Lafew, helps redeem that long unknotting of circumstances at the play's end with wit and irony. But the delicacy and restraint of this production are most visible in two performances--both of which are generally an invitation to fuss and bother: Lavatch, one of those punning fools, constantly underfoot, and Parolles, the yellow-bellied peacock.

Neville-Andrews has had the idea of turning Lavatch into a white-faced music hall clown with flowers up his sleeve and an expression of sweet woe on his face. As Jim Beard plays him, the character offers a lovely counterpoint to the play's harsher moods. There's something touching, too, about King's performance as Parolles. Exposed by Bertram and his men for the dolt and shivering coward he is, he shrugs in self-recognition, smiles a faintly shameful smile that implies all men can't be heroes, pulls himself up to his formerly foolhardy height and braves the future. The unadorned honesty of the moment is truly affecting.

With all its virtues, it should be noted that "All's Well" takes considerable time to get rolling and the second act is distinctly stronger than the first. But the evidence is beginning to pile up: Neville-Andrews' stewardship at the Folger has made a significant difference. ALL'S WELL THAT ENDS WELL. By William Shakespeare. Directed by John Neville-Andrews; sets, Lewis Folden; costumes, Bary Allen Odom; lighting, Hugh Leter. With Mikel Lambert, Peter Webster, Floyd King, Gwendolyn Lewis, Jim Beard, John Wodja, John Wylie, Thomas Schall, Craig Paul Wroe, Paul Norwood, Vivienne Shub, Gail Arias. At the Folger Theatre through June 19.