Suraj and Radha never know when the colourful 'Happiness Train' will chug into their village, offering them a whole new world of fun and enchantment! 'Trains and tracks are evil,' says Amma, 'they carry people away.' But this train's musical whistle, the gorgeous pictures on the coaches, and its promise of faraway exciting lands and the raja who owns them – all make Suraj eager to leave his humdrum life at home and set out on adventures. Ignoring Radha's warnings, he secretly boards the train. Soon Suraj realizes that things are not as they seem and that he and the other runaway boys – Murali, Chhotu and Asad – are being carted away on a dark, dangerous mission. With no hope of escaping, they are close to giving up when help arrives from an unexpected quarter. Is there a mysterious person on the train who can help them? How is the raja connected with the train? Has Radha forgotten all about Suraj? And does he finally get what he is looking for? Find out in this unusual story about family, friends, and discovering new routes to happiness and home.