The three-hander is the New Zealand debut for the Northern Lights production company, English director Alex Bonham and London actor Simon Kane (as Heisenberg), and they all deliver with aplomb.
Kane especially shows mastery from the start, and both he and Bruce Phillips as Bohr live their challenging dense paragraphs, exchanging them with rapid-fire excitement and clear enunciation.
The script cleverly see-saws its sympathy between Bohr and Heisenberg, while Margrethe, played by Jennifer Ward-Lealand as a shrewd observer, is more cipher than character.
Rachael Walker's satisfying conceptual theatre-in-the-round design places all the action on a gigantic hydrogen atom, using three black stools as sub-atomic particles (the costuming suffered a little in comparison). A ring around the claustrophobic nucleus is lit up like a fire, but the "firewood" is books and shoes: the Holocaust and Hiroshima press into the conversation.
Concentration is richly rewarded; have a coffee before you go. Recommended.
Copenhagen is on at Tapac, Western Springs, until June 10.