Paris, 1806. Michel Adanson is dying. The last word to escape his lips is a woman's name: Maram. Who was she? Why, in the course of his long life, has he never spoken of her before? As Adanson's daughter sorts through his things, she discovers a notebook. It reveals a secret history both fantastical and terrible, of his time as a young botanist travelling in Senegal. How Adanson first heard of the 'revenant': a young woman of noble birth, abducted and sold into slavery across the seas, who then did the impossible-she came back, to live in hiding. How he became obsessed with finding her, embarking on an odyssey that would lead to danger and destruction. How a man who longed to solve the mysteries of nature instead found himself faced with the uncontrollable impulses of the human heart. Tragic and tender, alive with feeling, this is a story of adventure, revenge and impossible desires, one which subverts our every expectation about who we are and who we love.