I have to admit - I am still a little baffled by this play, just as I was when I read Spies.
Copenhagen is a fact-based play about a meeting between Niels Bohr and Werner Heisenberg in 1941. It is non-linear, jumping between the first time the men worked together in the 1920, their meeting in 1941 and an unspecified later date. The men discuss the creation of atomic weapons, trying to piece together the sequence of events of their historic meeting in Copenhagen in 1941.
Heisenberg and Bohr conflict over what they remember from that fateful meeting in 1941. Neither recalls exactly what was said or what was intended - as explored in Spies, memory is never perfect.
The play is incredibly complex, both in terms of it's style and content. There are minimal stage directions and only three characters - Heisenberg, Bohr, and his wife Margrethe. All three remain on stage throughout, though sometimes the dialogue implies that the character talking might not be aware of the presence of others. This lack of formal structure means that the script has a lot of room in which the actors can play, presumably producing incredible theatrical shows. I think that seeing this on stage would definitely clear up some of my confusion.
Because the story is about science behind the atomic bomb, some of the language is incredibly jargonised. Much of the terminology was too difficult for me to understand, but beneath the physics was an exploration of memory and morality.
Undoubtedly, Michael Frayn is an incredibly well-educated writer, repeatedly exploring the flawed nature of memory and the significance of history. But this play was difficult to visualise - a stark contrast from other plays I have read recently in which stage directions bring to life the author's vision.