Constantinople, 672 AD. Ex-concubine Anna makes a living manufacturing perfume and attempts to raise her daughter well, while trying to keep it secret that Theodosia is really a prince's daughter. But as an Arab invasion threatens and Kallinikos - an alchemist working on a secret weapon to use in the siege - comes into their lives, her daughter's secret is forced into the open and Anna must accept a huge upheaval in her life, recognize her feelings for the attentive Kallinikos and rethink her determined independence...