'Legacy of Light'

Emilie du Chatelet, the heroine of "Legacy of Light," Karen Zacarias' smart and funny new play, is no ordinary woman. The 18th century French aristocrat, mathematician and physicist is busy translating Isaac Newton's ideas about energy and matter into French -- and expanding his work with her own theories.

But when we meet her in Arena Stage's world premiere production of "Legacy of Light," she is in the arms of her handsome young lover and discovered by her other lover, who happens to be philosopher, playwright and poet Voltaire. And a little while later, we meet her husband, the Marquis.

"We're French," Emilie (Lise Bruneau) and Voltaire (Stephen Schnetzer) explain as they address the audience for a nice bit of exposition about their lives and time.

As the play shifts deftly to our own time, astrophysicist Olivia Hasting-Brown (Carla Harting) is leading a life that is no less complicated. On the verge of what could be the discovery of a developing planet and in remission from cancer, she is searching for a surrogate mother to bear a child for her.

Olivia and her schoolteacher husband Peter (Michael Russotto) choose the engaging Millie (Lindsey Kyler) as their surrogate and begin trying to fit doctor's appointments, Lamaze classes and other baby-centered activities into their busy lives.

Emilie, too, is expecting, though at 42 with two grown children, she fears childbirth may threaten her life. As the births of their children near, both women are driven to complete as much scientific work as they can.

The regal Bruneau, who looks as if she was born to wear the sumptuous costumes designed for her by Linda Cho, brings to life Emilie's passion for her work and for those she loves. When she tells us that everything changes, but is never lost, she is referring to more than her discoveries about the conservation of energy.

Schnetzer's Voltaire is amusingly pompous, reminding us frequently that he is the "Father of the Enlightenment." But his depth of feeling for the beautiful and brilliant Emilie is never in doubt. Zacarias blesses these two characters with wonderfully witty repartee, and Bruneau and Schnetzer deliver it with grace and humor.

Under Molly Smith's able direction, the action alternates smoothly between 18th century France and present-day America, exploring the themes of science and love, drawing parallels and pointing to distinctions between the lives of these two women. Marjorie Bradley Kellogg's set adapts easily to the change in eras as a chandelier is lowered, an apple tree glides into place or a table is shifted slightly. The actors, most of whom do double duty, also seem to move effort-lessly between time periods.

Kyler bubbles as the eager and likeable Millie who has more reasons for becoming a surrogate she reveals to Olivia and Peter. She also portrays Emilie's beloved daughter Pauline, whose own future jeopardized by her mother's risky pregnancy.

David Covington doubles as Emilie's confidant and debonair lover St. Lambert and as Millie's less-self-assured brother Lewis, who has serious misgivings about her surrogacy.

Russotto plays two very different husbands: the Marquis du Chatelet and Peter Brown. The indul-gent Marquis allows Emilie her science and her lovers, provided he has his own freedom. But he is willing to put in an appearance for propriety's sake when she finds she is expecting and to join forces with her to secure the children's future. Russotto's Peter is a bit bumbling, but very nurturing. In fact, it this quality that gives Olivia the courage to attempt parenthood despite the threat of a recurrence of cancer.

But it is also Peter's enthusiasm for the baby that gives Olivia pause. Her natural enthusiasm is for science. In a passionate speech about dark matter and other scientific fields of study she delivers to a group of Girl Scouts, it is the embryonic planet that she refers to as her baby. And she fears that she won't be a good mother to her human baby. Harting, who also ap-pears briefly in an 18th century scene, is moving as she confronts the modern-day demands of career and parenthood.

Both Emilie and Olivia and their stories are compelling, but the play reaches new heights when their worlds collide -- improbably and delightfully -- under that apple tree.

WANT TO GO?

» WHAT'S UP: "Legacy of Light"

» WHEN: Through June 14

» WHERE: Arena Stage, 1800 S. Bell St., Arlington

» TICKETS: $25 - $66

» INFO: www.arenastage.org or call (22) 488-3300