Aksharathettu

While his wife Sumathi (Urvashi) & son was out of town, happily married bank manager Prakash (Suresh Gopi) gets trapped into a one-night stand with Renuka Nair, a rich widow whom he had recently met at the bank. Immediately after the encounter, a guilt-ridden Prakash wants to put the experience behind him & move on, but Renuka refuses to let go of their relationship. Driven to madness by his rejection, she turns to violently harassing both Prakash & his family. (Summary by iceblox)