The makers of Tamil film Yaan have sent a legal notice to its director Ravi K Chandran, alleging that his work is a blatant copy of 1978 British film Midnight Express.
They discovered the similarities recently.
Renowned cinematographer Chandran made his directorial debut with Yaan, which released worldwide in October 2014.
While the initial reviews of Yaan hinted that the film was based on Midnight Express, the makers didn't pay heed.
"It was only after someone uploaded a video on Youtube comparing our film with the original, we realised that he had copied. We were shocked because he (Ravi Chandran) told us that the film was inspired by a true incident and is entirely original," said the film's producer Elred Kumar.
"We feel that the producers of the original might file a lawsuit. Before they do, we've sent a legal notice to Ravi Chandran for breaching the agreement he had signed that the story is original. He should be held responsible, not us," he said.
Producer Kumar added that they're yet to hear from Chandran on the notice.
Chandran was unavailable for comment.
Starring Jiiva and Thulasi Nair in the lead, Yaan is the story of a guy who gets busted for possession of drugs in foreign land.