Portal

The sequel to Boundary and Threshold. New York Times Best-Selling Author and a Rising Star of SF and Fantasy Continue their Popular Space Adventure Series.The sequel to Threshold, Book Three in the Boundary series. HELL FROZEN OVERMadeline Fathom had miraculously landed the crippled Nebula Storm on Europa. She joined on that frozen moon of Jupiter the stranded crewmembers of the ill-fated EU vessel  Odin. The Nebula Storm's reactor was ruined in the landing, the Odin’s shuttle can’t make the trip back home, and the only vessel that could have make the journey to save them has just been destroyed by a renegade crewman, bad luck, and the remorseless forces of nature.But Madeline, Helen Sutter, A.J. Baker and the team have one card left to play.