After his heroics aboard the Hibernia in Midshipman's Hope, Nicholas Seafort wins command of his first ship, the Challenger, and joins Admiral Tremaine's task force. Their first meeting is a rude awakening, however, as Tremaine demotes him to a smaller, overcrowded ship and blatantly ignores Seafort's report of alien life on Hope Nation. Above all, Seafort is anxious for his pregnant wife, who's due to have their baby on the journey. After an alien attack and an admiral's betrayal, a wounded Seafort is left stranded aboard a ship short of weapons and fuel. Hundreds of lives hang in the balance as Seafort must find a way to survive.