The book unfolds by first establishing the lighthouse as a symbol of safety, contrasting this with the reality of nearby shipwrecks. Subsequent chapters then investigate particular lighthouses linked to maritime disasters, assessing environmental conditions, technological shortcomings, and human factors. Ultimately, Beacons of Doom underscores the ongoing need for vigilance and innovation in maritime safety, demonstrating that even the most advanced technology cannot eliminate the risks posed by nature and human fallibility.