Ek tells the story of a hired assassin who unexpectedly finds love and a family. Nandu (Bobby Deol) is an orphan who enters the world of crime as a boy. He murders his first victim at the age of nine and grows up to be a cold-blooded assassin.
A political leader, Anna Mhatre, hires Nandu for a unique job. He wants Nandu to make a fake assassination attempt on him while he is addressing a rally for his election campaign. Mhatre`s motive is to create a sympathy wave he can convert into an overwhelming victory.
But things go horribly wrong, and Anna Mhatre is actually murdered. Nandu makes a quick getaway and manages to find a hideout and a family, after he is mistaken for a Punjab boy by an unsuspecting family. But the cops are close on his tracks, and Nandu is left with no choice but to find the truth behind Mhatre`s murder.
Director Sangeeth Sivan would be returning to the action genre after a decade since he made his Bollywood debut with Sunny Deol starrer Zor.