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

'Propulsive…entertaining and enjoyable' Financial Times

'A dazzling novel' Independent

'Haunting, playful and ultimately hopeful… A wonderful book' Kaliane Bradley

'A poignant love letter to the vanishing past' Guardian

*A BOOK OF THE YEAR for the Sunday Times, Guardian, New York Times, New Statesman, Spectator, New Yorker, i Paper and Barack Obama*