Post Box No. 999 is a 1958 Hindi murder mystery thriller directed by Ravindra Dave and produced under Nagina Films. The film stars Sunil Dutt as Vikas and Shakila as Neelima, with Leela Chitnis in a key role. The story follows a determined reporter who investigates the case of a man accused of murder. The investigation revolves around mysterious clues linked to Post Box No. 999, leading to a suspenseful unraveling of secrets and hidden motives. As the reporter digs deeper, the plot thickens with deception, danger, and unexpected twists, keeping the audience engaged until the final reveal.

The film’s music by Kalyanji-Anandji heightens the suspenseful mood, while Shakila delivers a standout performance. Post Box No. 999 is regarded as a compelling murder mystery thriller of the 1950s and reflects the era’s growing interest in investigative suspense stories in Indian cinema.