Tannin is the secret scaffold of red wine—what you cannot see but certainly feel. From grape skins and seeds to oak barrels, a journey through the chemistry and sensory experience of the substance that distinguishes a forgettable bottle from one capable of traversing decades.

Technology has revolutionised grape harvesting, yet hand-picking remains irreplaceable where vertiginous slopes and terraces make mechanisation impossible. From Champagne to Valtellina, a journey through expert hands and optical sorters to discover when the way a bunch is picked truly makes a difference.

Why do the world's finest wines emerge from places where labour is hardest? From the vertiginous slopes of Germany's Mosel to the dry-stone terraces of Valtellina, this journey explores how gradient, aspect and the slow rhythm of ripening shape the character of wine in the glass.