Stealer: The Treasure Keeper follows the double life of Hwang Dae-myung, a seemingly lazy and unremarkable civil servant at the Cultural Heritage Administration. By night, he transforms into the mysterious thief 'Skunk,' a vigilante who specializes in recovering stolen cultural assets from corrupt high-ranking officials who have illegally hoarded national treasures for their own gain. As Skunk continues his high-stakes heists, he crosses paths with 'Karma,' an unofficial recovery team within the Seoul Metropolitan Police Agency. Together, they must navigate a dangerous web of greed and power, uncovering the truth behind the seven mysterious 'Joseon Numismatic' coins that hold the key to a massive conspiracy. The series blends action, comedy, and mystery as Dae-myung balances his mundane office life with his dangerous quest to restore Korea's stolen history.