Romeo S3 is an action drama about DCP Sangram Singh Shekhawat (Thakur Anoop Singh), a tough and tenacious policeman who is committed to taking down a significant drug cartel that has engulfed the city in addiction and terror. When he encounters Priya Mehra (Palak Tiwari), an investigative journalist seeking the same facts from the other side of the law, his journey takes a dramatic turn. Their tense partnership leads to some vital clues that help get rid of the drug mafia.