Vairam is the Tamil remake of the highly successful Hindi movie ” Victoria 203″. The story revolves around a horse drawn cart , whose driver (Sahasranaman) witnesses a gang shoot out and murder of one of the gangsters. He gets falsely implicated in the murder and goes to jail. The murdered gang member before dying hides a pouch of diamonds in the lamp of the horse cart without anyone’s knowledge. Jayalalitha , the cart driver’s daughter disguises herself as a man and drives the cart around the town for a living. In one of her outings, she meets with Jaishankar, son of the rich gang leader and both fall in love. In the meanwhile, two convicts ( Asokan and MRR Vasu) , just out of jail accidently get hold of a locker key which leads them to a clue where the diamonds are hidden. The gang leader , in the meantime launched a massive search for the diamonds and kidnaps the convicts and Jayalalitha to extract the truth. Jaishankar fights the gang and retrieves the diamonds and hands over to the police. He also learns that his real father was one of the convicts, MRR Vasu and gets united with him. Jayalalitha’s father gets released and all ends well.