In 1958, on the outskirts of Paris, Monsieur Julevere operates a distinguished restaurant catering to the city's elite, renowned for its impeccable discretion and refined service. One of his unique traditions is assigning fictional English surnames to his guests, inspired by his admiration for English war heroes. One fateful evening, an enigmatic man named Mr. Ceasar-soon nicknamed "Mr. Churchill"-arrives and makes an unusual request: the last bottle of a rare Champagne, paired with a simple boiled potato. This peculiar order ignites Julevere's obsession with mastering the perfect preparation of the humble potato, especially when he discovers that "Mr. Churchill" is, in fact, a celebrated potato magnate offering a million-franc reward for culinary perfection.

Julevere's pursuit takes him on a whirlwind journey, blending culinary experimentation with the mysteries of history. The quest leads him to explore the continent from which the potato originates, the revenge of Montezuma, and the hidden legacy of his dishwasher Alfonso, whose Inca ancestry may hold the key to the perfect potato. Meanwhile, an accidental turn of events catapults the potato into the Cold War's space race, entangling it in the USA and USSR's most ambitious programs.

As Julevere's obsession deepens, it upends both his personal and professional life. Will he finally uncover the secret to serving the perfectly boiled potato with a glass of exquisite Champagne-or will his ambitions crumble under the weight of his own perfectionism?