Chennai, March 19: An old email from a friend has helped Malayalam film director Jeethu Joseph win a plagiarism case against him, satisfying the court the screenplay had been written before the plaintiff's book was published.

Fellow Malayalam director Satheesh Paul had approached a court in Ernakulam claiming Joseph's highly acclaimed film Drishyam was based on his book Oru Mazhakaalathau (Rainy Days), released in June 2013. Drishyam, starring Mohanlal, had released in December 2013 and become a runaway hit.

Paul also sought an injunction against the Tamil version of the film, Papanasam, starring Kamal Haasan and directed by Joseph.

Since the shooting of the Tamil film had already begun, the court refused to grant a stay but asked the producers to furnish a bank guarantee of Rs 10 lakh.

"Initially, I was disturbed by the case but Kamal Haasan urged me not to give in. He said his film Dasaavathaaram too had been dragged to court but he was able to disprove the plagiarism charges," Joseph told The Telegraph.

"We had erected sets (for the Tamil version), paid a month's rent to hotels and booked flight tickets. So a stay would have led to a loss of Rs 20 lakh. But producers Suresh Balaje ( Papanasam) and Antony Perumbavoor (Drishyam) stood by me, urging me to disprove Paul's claim."

Joseph said the judge found his script vastly different from Paul's book, but what nailed the case was an email.

"I had handwritten Drishyam and sent it to a childhood friend in Elanji (Ernakulam) who runs a desktop publishing centre," the director said.

"He emailed me the soft copy of the script in September 2011. When we produced the email record from my friend's 'sent' folder, the judge was fully convinced that the script was indeed mine. He had no hesitation in dismissing the case."

Joseph plans to file a defamation suit against Paul.

Drishyam tells the story of a middle-class man who hides the body of his daughter's blackmailer and creates layers of alibi to fool the police, who fail to prove the case against him as the body remains undiscovered till the end.