a thirty-five-year-old Patrician is unexpectedly appointed co-emperor by the Senate, with his father, Valerian. He is an unlikely choice with his Greek education, sardonic personality and his reputation for frequenting brothels and taverns, behavior considered scandalous by his contemporaries.

The following spring Valerian goes east to contain an aggressive Persian king, placing Gallienus in command of the western empire. With a significant portion of the army in Syria and a virulent plague sweeping through the empire, Gallienus has insufficient manpower to defend Rome's entire northern border.

Rome relies on provincial governors to defend their assigned regions due to the empire's size. Thus, Gallienus must share power with men strong enough to defend their provinces and yet remain loyal to him. Unfortunately, he selects some men who prefer the title of emperor to that of governor or general. In the previous forty-two years fourteen emperors have died violently-all but one killed by other Romans.

Gallienus finds himself in a desperate struggle to defend the empire against numerous invading tribes and suppress civil wars threatening his reign from within, sometimes simultaneously. When not on the battlefield, he must deal with intrigues of ambitious men in a restive Senate. He enjoys the company of women and values their counsel. Yet among these tempting women are those willing to use any means available to advance their own interests. His survival depends on the enemies he makes and the people he trusts.