In Basra, a young scholar believes the world can be understood. But in Cairo, Ibn al-Haytham’s certainty shatters.

Summoned by the unpredictable Caliph Al-Hakim to tame the Nile, he realizes that he cannot. With failure carrying a potentially fatal price, he chooses disgrace over death and retreats into confinement.

Stripped of his reputation and freedom, Ibn al-Haytham is left with the steadfast Lady Zaynab, whose wit and loyalty sustain him through his darkest days. Then, a beam of light enters a shadowed room and presents him with a question that centuries of accepted wisdom cannot answer.

As Ibn al-Haytham begins to see light, vision, and truth in radically different ways, he discovers that understanding the world may require admitting when you are wrong.