Among the glacier mountains and frigid waters of Antarctica, Deb Gardner and Keller Sullivan feel at home. For the few blissful weeks they spend each year studying the habits of penguins, Deb and Keller can escape the frustrations and sorrows of their separate lives and find solace in each other. But Antarctica, like their fleeting romance, is tenuous, imperiled by the world to the north.A new travel and research season has just begun, and Deb and Keller are ready to play tour guide to the passengers on the small expedition ship that ferries them to their research destination. Except that this year, Keller fails to appear on board. Shortly into the trip, Deb's ship receives an emergency signal from the Australis, a cruise liner that has hit desperate trouble in the ice-choked waters. And among the crew of the sinking ship is Keller...As Deb and Keller's troubled histories collide with this catastrophic present, Deb's role turns from researcher to rescuer all too aware that in this land of harsh beauty even the smallest missteps can have tragic consequences.