(FORTUNE Magazine) – I didn't see Copenhagen on Broadway last year, but reading the script is a way of pondering one of the murkiest, most profound incidents of modern times. In 1941 Werner Heisenberg, the leading physicist doing atomic research for the Nazis, went to Copenhagen to meet with his mentor, Niels Bohr. What was said, and meant, is a mystery--even though both later tried to explain what had occurred. Was Heisenberg hoping to learn about Allied efforts to build an atomic bomb, or was he trying to convey a message that he was subtly sabotaging Nazi research? And was he really sabotaging the efforts or just pretending? As the questions unravel, each possible answer produces even more questions.

Michael Frayn's play (Anchor Books, $12) has only three characters--Heisenberg, Bohr, and Bohr's wife, Margrethe. They're all now dead, meeting up in a hazy limbo where they try to sort out what happened that evening in 1941. Frayn brilliantly makes the science clear while creating an absorbing drama of guilt, identity, and the limits on our ability to understand the universe or the person standing in front of us.

If Copenhagen whets your appetite for science, you can feast on The Best American Science Writing 2000 (edited by James Gleick; Ecco Press, $14). Which determines our behavior--genes or environment? Did a guiding hand shape the universe? Was there such a thing as Stone Age couture? And perhaps most important, what can science tell us about insoles? The essays give contemporary science's best answers to these eternal riddles.