In Treasure Town, two orphaned street kids, Black and White, navigate daily survival with a mix of innocence and street smarts. While White is carefree and naive, Black is fiercely protective and assumes the role of White's guardian. Together, they are known as the Cats, ruling the streets with a blend of whimsy and violence. Their unorthodox family is tested when the yakuza and foreign entrepreneurs vie to take over Treasure Town for their commercial interests. This encroachment threatens the duo’s way of life and the balance of power in the city.

As external forces close in, the bond between Black and White is strained. Black's willingness to do whatever it takes to protect their home and White pushes him toward darker actions, contrasting with White's purity and simple outlook on life. The arrival of a pair of mysterious assassins further complicates matters, challenging the brothers' resolve and their grip on reality. The urban tale unfolds amidst visually stunning sequences, exploring themes of loyalty, survival, and the loss of innocence in a changing world.