The dusky blue waters of Lake Victoria stretch lazily across the verdant plains of Tanzania, but beneath the placid surface a massacre has taken place. In the 1960s, the Nile perch, an enormous variant of the American variety, was experimentally introduced into the lake, and since then it has wiped out practically all other marine life. While spelling disaster for local communities, the situation has proved a bonanza for the multinational fish factories that process and ship tons of perch abroad. Thus does globalization feed its lucrative foreign markets while the locals starve to death. Hubert Sauper’s fascinating film reveals the effects of this ‘un-natural disaster’ — the consequences of reckless economic development that cared little for local ecology and even less for the people whose lives would be affected.