S1, E101: A million flamingos congregate on a steaming soda lake in Africa’s Rift Valley. Baboons and Fish Eagles are attracted by the huge pink flock. While there is strength in numbers, it's inevitable that some flamingos will die today – but which ones will it be and why? Each day these birds put themselves at risk by filtering away from the vast flock and into a particular danger zone – a cul-de-sac. Here live a troop of baboons with a unique skill – they are flamingo killers. The baboons scan the flock for a likely victim – strength in numbers is critical now but how does an individual flamingo manipulate its position in the flock to avoid becoming a victim? Also: the mass movement of migrating wildebeest across the Serengeti is thought to be the greatest movement of land animals anywhere on Earth. But what happens when almost two million animals come up against the bottleneck of the Mara River and its giant crocodiles that guard the crossing points? In some of the most extraordinary and dramatic wildlife scenes ever filmed, we discover what drives the wildebeest to jump into the crocodile infested water, whether there is anything an individual could do to maximise its chances of survival. Do they work together as a herd, or is it each wildebeest for himself? It's crunch time for the crocodiles too – they need this annual feast to survive. We reveal the attack strategies that these cold-blooded reptiles employ.