In a world submerged by rising seas, can the secrets of the past be discovered? The breathtaking Sunday Times bestseller.
 
‘Full of wisdom and heart. I loved it’
Elif Shafak
 
‘A gripping page-turner’
Observer
 
‘It gave me so much pleasure’
New York Times
 
2014: A great poem is read aloud and never heard again.

For generations, people speculate about its message. 2119: With the UK’s lowlands submerged by rising seas, those who survive are haunted by all that has been lost. Tom Metcalfe, a university scholar, pores over the archives of the early twenty-first century.

When he stumbles across a clue that may lead to the lost poem, he reveals a story of entangled love and a brutal crime that challenges everything he thought he knew about the past.
 
‘What We Can Know may well have created a new genre’
Sunday Times‘Brilliantly plotted… In What We Can Know, the past is an irresistible riddle’ Washington Post