Returning from an anti-war demo, Gary (Danny Dyer) and four friends stop briefly in the countryside. Breaking from the group, Derek (Jimi Mistry) and Saffron (Lois Winstone) find a metal hatch in the middle of the forest, and decide to explore inside. Searching for their missing friends, Gary, Pru (Emily Beecham) and Sarah (Kierston Wareing) are forced to follow, but as the hatch locks behind them all, the shadows that lurk in the darkness force the whole group to run for their lives...