After appearing in a supportive role in English movie Mother Teresa: In the Name of God's Poor in 1997 Nimmi made her first step in to the Sri Lankan cinema in 2003 by playing the lead role in Prasanna Vithanage’s film Ira madiyama (August Sun) where she portrayed a role of a woman whose husband is missing in action. Her successful performance throughout the movie brought her positive critics and several accolades, including the Best Actress award at the 2004 International Film Festival in Spain. Following Ira madiyama, she appeared in her next television film Mother Theresa in the same year which was filmed in Sri Lanka and Italy. In 2009 she appeared in her first Tamil speaking role in Enakkum oru per (I Too Have a Name), a short film which was nominated for the Golden Bear for Best Short at the Berlin International Film Festival in Germany.
