Joe Herman, John Barker and Susan Blair are seen here in “Copenhagen,” now at Stagecrafters, 8130 Germantown Ave., through June 23. It won the Tony Award for Best Play; also Best Play awards from the Drama Desk and New York Drama Critics’ Circle. (Photo by Sara Stewart)

by Hugh Hunter

“Copenhagen” (1998), by English playwright Michael Frayn, won the Tony for Best Play during its 2000 Broadway run. Director David Flagg brings this inventive play to Stagecrafters, where the mystery of quantum physics and the mystery of human behavior confront each other like reflecting mirrors.

In her opening line, Margrethe Bohr asks: “Why did Heisenberg come to Copenhagen in 1941?” Did he want Bohr’s absolution for working on Germany’s A-bomb project? Was he spying? As in quantum physics, the questions are more surefooted than the answers. The play’s three characters circle around each other like orbiting electrons, recollecting past events from different times and different viewpoints.

A backdrop collection of blackboards with chalked math equations dominates Patricia Masarachia’s set. As Werner Heisenberg, John Barker delivers a mountain of dialogue without flubbing a word. Though Heisenberg has wild mood fluctuations, anguish is prominent. Barker makes the most of a bare stage; his wide range of movement reflects Heisenberg’s inner turmoil.

You discover the grounds for his despair and are surprised to find how well science-laden dialogue can hold your attention. Before the show and during intermission, Flagg’s stage apron videos help out by explaining the real-life history of the Bohr-Heisenberg relationship as well as core concepts of quantum physics.

You learn that between 1924 and 1927 they developed the “Copenhagen Interpretation” that laid the groundwork for quantum physics. Bohr’s “complementarity” argues that the dual particle and wave properties of light also describe sub-atomic matter; Heisenberg created the “Uncertainty Principle” to argue that you cannot simultaneously determine both velocity and position because of the “observer effect.” (Modern physics has both upheld and amended his ideas.)

But spooky (to use Einstein’s word) as this quantum world is, it is not any stranger than human relationships. What do we want? What do we want from each other? Joe Herman as Niels Bohr is the perfect counterpoint to Heisenberg. Half-Jewish, he is also emotional but with a more secure sense of moral rightness. Susan Blair as Margrethe Bohr is a strong woman who breaks up their science quarrels with down-to-earth observations about vanity and ambition.

Playwright Frayn has a genius for coming up with clever conceits. He also wrote “Noises Off,” a smart, innovative farce in which behind-the-scenes mayhem mirrors the antics on stage. In “Copenhagen,” coupling the weirdness of quantum physics with our interpersonal strangeness is a brilliant leap of imagination.

Hollywood producers use the term “high concept” for similar cleverness in movie scripts (“The Sixth Sense”, for example). But Frayn’s conceptual gifts are stronger than his knack for storytelling. His plays are cluttered, diluting the dramatic impact of their many delicious ironies. “Copenhagen” is a very good play, both metaphorical and provocative. Annoyingly, it stops just short of being a great one.

Stagecrafters is located at 8130 Germantown Ave. “Copenhagen” will run through June 23. Tickets available at 215-247-8881.