The Sin (2007)

A young boy accidentally kills a woman by dropping a fire extinguisher from an apartment building. Because of his age, he is not held responsible. Ten years later, a string of murders targeting young girls begins. The boy from the original incident becomes a suspect in the new crimes, while the murdered woman's son witnesses one of the murders. When the two families reunite, a clash of ideologies emerges: one advocating for harsh punishment beyond the legal system, and the other opposing revenge.