After avoiding an arranged marriage, thwarting a coup, and inadvertently kick-starting a revolution, Rory Thorne is no longer a princess, but a space pirate.
Her new life is interrupted when Rory and her crew—former royal bodyguards, Thorsdottir and Zhang, and co-conspirator Jaed—encounter an abandoned ship registered under a false name, seemingly fallen victim to attack. As they investigate, they find evidence of vicious technology and arithmancy, alien and far beyond known capabilities.
The only answer to all the destruction is the mysterious, and unexpected, cargo: a rose plant. One that reveals themself to be sentient—and designed as a massive biological weapon. Rose seeks to escape their intended fate, and Rory and her friends must act fast when the attackers return with their superior weaponry.
As the situation gains the attention of an increasing number of alien races, Rory finds herself acting as negotiator and diplomat, in order to save Rose and her friends—and avert an unprecedented war.