At 70, Biana Watre Momin took a leap far from home. The retired college teacher left the Garo Hills in north-eastern India's Meghalaya state, where she led a quiet family life - caring for four dogs and doting on her grandchildren - and travelled more than 3,000km (1,864 miles) south to Kerala to act in a film. She was dealing with a language she did not understand, embracing a role whose meaning would only reveal itself once the camera began to roll. The film was Eko, a Malayalam-language film