Vishwaroopam story begins on the backdrop of America and here lives Viswanath (kamal) who is a Kathak dance trainer. He is married to Nirupama (pooja) who comes to US only for her career and marriage is just for understanding. Though they don’t share any marital relationship, she also hires a detective to trace the movements of Viswanath. The story takes a turn when both Viswanath and Nirupama’s paths cross Omar (Rahul Bose) who is a terrorist mastermind. What happens after that forms the rest of the story.