Chronicles of the Imperial Rangers — Barbara Robertson

Great Benevolent Empress Kayla has disappeared. She and her Son, Prince Lukus, the Royal Heir to the throne, are in grave danger. The Imperial Rangers and Military frantically search the solar system for their missing Sovereign, knowing she has fallen prey to the evil, mysterious Figure Thirteen.The nefarious Plan of the Thirteen is at work, its traitors carrying out their detailed plans developed thirty years ago to take control of the Empire and give the throne of power to one of their own. Their secret weapon to defeat the Imperial Military is the Old Engine, capable of destroying the military might of the Empire.The Imperial Rangers and First Consort Master Commander Dan'L lead the defensive efforts to find Empress Kayla before she is killed and replaced by one of the vengeful Plan of the Thirteen conspirators. Failure means the destruction of the Great Empire and their world. The Rangers must succeed at any cost.Plan of the Thirteen is the exciting and action-packed third novel of the series, Chronicles of the Imperial Rangers.