Beating the odds against the predators on Tanzania's Serengeti Plain and the Kenyan Masa Marai, the wildebeest calf has survived the first part of the huge 3000 km round trek with his mother and the herd. But the crossing of the Mara River presents the biggest challenge yet for this fragile little creature. Its raging torrents are a death trap and there are crocodiles galore waiting to pick him off. Croc cam, skullcam, tortoisecam and hippocam, filming from ground level camouflaged cameras, capture all the drama and danger up close as the herd run the gauntlet of their land and water enemies for their annual epic mission.