N.K. Salil, a Bengali screenplay and story writer, started his career at the age of 17, starting with writing scripts for Akashbani. After assisting on a handful of television serials, Salil made his debut as a screenwriter in 1998 with the Prosenjit Chatterjee-directed Indo-Bangladesh movie Ami Sei Meye. He then went on to be associated with movies such as Shatruta, Harjeet, Sonar Sansar, Annadata, Rakhe Hari Mare Ke, Barood, Coolie, Sathi Amar, Rajmohol, and Cheetah.
In 2005, he made his acting debut with the movie Yuddha, which he was also associated with as a writer. Since then, he appeared in several movies such as Yuddho, MLA Fatakeshto, Tulkalam, Premer Kahini, Chirodini Tumi Je Amar, Mon Mane Na, Kellafate, and Ami Je Ke Tomar, also writing down their script/story/dialogues. Meanwhile, he continues to be associated with movies as just a writer and was a part of successful projects such as Challenge 2, Rocky, Boss, Rangbaaz, Arundhati, Besh Korechi Prem Korechi, Kelor Kirti, Haripada Bandwala, Jio Pagla, Ghaire & Baire, Girlfriend, Bagh Bandi Khela and Kidnap.