The last of the Arctic terns are embarking on what may be their final migration to Antarctica and Franny Lynch is determined to follow them. She talks her way onto the Saghani, one of the last certified boats to fish for Atlantic herring, and together with the crew she sets off south. As Franny follows the birds, she is forced to overcome the hindrances that threaten to offset her course, and the relentless devastation of her past.