Chennai, Feb 28 (IANS): The much awaited trailer of ace filmmaker Mani Ratnam's Tamil romantic-drama "Ok Kanmani", which features Dulquer Salmaan and Nithya Menen in the lead, will be unveiled online Sunday.

"The trailer will be launched March 1. The film will hit the screens in April. The team is currently busy with the post-production work," a source from the film's unit told IANS.

Said to be a campus love story laced with comedy, the film will mark Ratnam's grand comeback to the romance genre after a decade. His last romantic outing was R. Madhavan-starrer "Alaipayuthey", which was later remade in Hindi as "Saathiya".

Ratnam is planning to release "Ok Kanmani" April 14, which marks 15 years since the release of "Alaipayuthey".

"While it was decided right at the beginning that the film will release in April, it was recently that Mani realized if released April 14, it will be the perfect tribute to one of his biggest hits 'Alaipayuthey'," the source said.

The film has music by A.R. Rahman and also marks the reunion of Ratnam with lensman P.C. Sreeram after a decade. It's touted to be Mani's quickest projects and is said to have been completed in about two months.

Some crucial portion of the film was shot in Mumbai, IIM Ahmedabad campus as well as CPET University. Nithya plays an architect in the film and renowned Indian architect B.V. Doshi plays her professor.