Ram Lakshman
Lakshman, an elephant, and Ram are inseparable friends. Ram even refuses to marry Meena when her father insists on getting rid of Lakshman. When Ram is accused of murder, Lakshman comes to his rescue.
Starring Kamal Haasan, Sripriya, S. A. Asokan, Thengai Srinivasan, V. Gopalakrishnan, Pandari Bai, M. N. Nambiar, Suruli Rajan
Watch "Ram Lakshman" on Amazon released in 1981. It's a drama movie, and has a rating of 7 out of 10 from Imdb which is usually fine for this kind of movie, and is currently only available for purchase or rent.