Deep Trap and The Housemaid are both psychological thrillers that focus on manipulation and power imbalance rather than conventional horror elements. In both films, tension is built through atmosphere and character dynamics, with discomfort playing a central role in the experience.
Tomorrow has the same two actresses, Kim Hee Sun & Kim Hae Sook they both work well together in both series. Room No. 9 is about a soul switching event that changes the lives of both of the actresses. Tomorrow is about grim reapers saving souls. both have their sci-fi elements but Room No. 9 is limited in it's science fiction but it plays out pretty good.
I'm sure if you enjoyed one you'll enjoy the other.
I'm sure if you enjoyed one you'll enjoy the other.

