After detaining the killer it seems that Marina will be forced to give up her dream of becoming a cop, but thanks to Castaño the case is reopened. Together they conclude that the killer is still on the loose and the cops propose a plan to catch him: host a masked party for the clients of the House of Water.

Now that they know where the killer's next victim is, they must get to her before the killer does. But just as Marina is beginning to gain her trust, the masked killer appears. Marina manages to save Margó and promises to give her protection. But Marina will soon discover that no one is who they claim to be and she shouldn't trust the people around her.