Invisible Executioner

S4, E3: Extreme angler Jeremy Wade travels to the Zambezi River in Africa after hearding tales of an invisible predator that drags fishermen to their deaths. Cases of crocodiles and hippos who kill people in broad daylight on the banks of rivers are not uncommon, but there is something extremely sinister about a killer fish stalking these deep waters. The locals describe this beast as the Mazunda - but does it actually exist? The Zambezi can be a treacherous river with plunging gorges and boat battering rapids and can be extremely dangerous. But when Jeremy hears a graphic eyewitness account of the deadly exploits of the Muzunda, his curiosity gets the better of him and he takes to the waters.