Stella Carey exists in a world of night. Married to an ex-soldier, she leaves the house every evening as Vincent locks himself away, along with the scars and the secrets he carries. During her nursing shifts, Stella writes letters for her patients to their loved ones, some full of humour, love and practical advice, others steeped in regret or pain and promises to post these messages after their deaths. Until one night Stella writes the letter that could give her patient one last chance at redemption, if only she delivers it in time.