Three Days Before I Sealed the Basement

Reborn after being murdered by her housekeeper's family, heiress Serena wakes up 3 days before her death. Learning the housekeeper drugged her and hid 5 relatives in her basement, Serena pretends ignorance and seals the basement with solid concrete. The intruders suffocate inside. Exposing their theft and plot, Serena sends the housekeeper to prison.