The Museum of Unclaimed Luck follows 14-year-old Leo, who takes a boring summer job in a dusty basement archives. He quickly learns it's not a regular museum; it houses the physical objects connected to "e;missed"e; moments of fortune—a winning raffle ticket left in a pocket, a coin that should have been found, a letter that got lost in the mail. Leo discovers he has the rare ability to "e;activate"e; these items and return the luck to the person it was meant for. But the universe demands a balance: every time he grants a piece of "e;Unclaimed Luck,"e; he must personally absorb a piece of "e;Residual Misfortune."e; Leo and his friends must decide if changing people's lives is worth the cost of their own bad luck.