“Tian Tong Yuan” is the life of the group-renting north drift graduates in Beijing. With my 4-month exprience living there together with them, I shoot this documentary, which describes the life of the north drifts graduates living in cellar. It reveals tha fact under the big pressure in finding jobs and high house prices, the 'ant tribe' have to live in a poor condition and have to face the great contrast between the dream after university graduation and the true world.For them, the glory of 'the chosen one' had already faded away and the life of being a 'north drift' make them struggle for survival. How to climb out of the underclass is the qusetion just as how to move out of their cellars, making them entangled every day. It is also worth thinking that can knowledge really change fate?