1942. Hannah Martel has narrowly escaped Nazi Germany after her fiancé was killed in a pogrom. When her ship bound for America is turned away at port, she has nowhere to go but to her cousin Lily, who lives with her family in Brussels. Fearful for her life, Hannah is desperate to get out of occupied Europe. But with no safe way to leave, she must return to the dangerous underground work she thought she had left behind.Seeking help, Hannah joins the Sapphire Line, a secret resistance network led by a mysterious woman named Micheline... A powerful novel about love, family and the unshakable resilience of women in even the hardest of times.