Nenjam Marappathillai offers a gripping narrative with a blend of horror and emotional drama. The story is engaging, with Selvaraghavan's screenplay effectively building suspense and intrigue, especially in the first half. The pacing is deliberate, allowing the tension to simmer, though some viewers may find the second half slightly slower as the plot delves deeper into emotional backstories.

The film’s cinematography by Arvind Krishna enhances the eerie atmosphere, complementing the horror elements well. Yuvan Shankar Raja's music and background score are standout aspects, intensifying the mood and elevating key moments, particularly in the haunting sequences. The songs are minimal but fitting, maintaining the film’s dark tone without disrupting the narrative flow.

Overall, Nenjam Marappathillai balances horror thrills with emotional depth, though the screenplay occasionally leans heavily on melodrama. The director’s vision is clear, and the technical aspects like sound design and visuals contribute significantly to the immersive experience.

S. J. Suryah: Delivers a restrained yet impactful performance, effectively portraying a complex character caught in supernatural turmoil.

Regina Cassandra: Offers a convincing and emotionally charged portrayal, anchoring the film’s emotional core.

Nandita Swetha: Provides strong support with a nuanced performance that adds depth to the narrative.

Arvind Krishna: Handles his role with subtlety, contributing to the film’s tense atmosphere.