Ranmuthu Duwa (English: Island of Treasures) was the first colour full-length Sinhalese language film to be produced in Sri Lanka in 1962. It was produced by Shesha Palihakkara and directed by Mike Wilson, who also made his debut as a feature director. The film stars some of those who would go on to become big names in the Sinhala Cinema, such as Gamini Fonseka, Joe Abeywickrema and Jeevarani Kurukulasooriya in the leading roles. Playback singing was by Nanda Malini, Narada Disasekara and W.D. Amaradeva. Lyrics were written by Chandrarathne Manawasinghe. It was an instant hit among the audiences and some of its songs are still famous today.
The film was shot in and around Trincomalee, Eastern Sri Lanka. It was shot on a 36-mm film and was the first Sri Lankan film to involve underwater scenaries