Sudeep is a high profile industrialist. He gets whatever he wants and he has a special eye for beautiful women. To get a girl, he wouldn't hesitate to do anything. That desire gets triggered when Sudeep sees Bindu, a micro artist who runs a non-profit organization. However, Bindu is loved by Nani who keeps following her everywhere. Bindu loves him but she doesn't express it to him and enjoys the attention.
The story takes a turn when Sudeep discovers the feelings of Bindu for Nani and couldn't digest his defeat. Sudeep kills Nani with his bare feet on Nani's throat. The next morning, Bindu finds Nani dead and is depressed.
Nani is born again as Eega (a house fly) and he (the fly) takes revenge on Sudeep with Bindu's help.
More here: http://en.wikipedia.org/wiki/Eega