Nature Shock: The Black Tip Shark Mystery, Channel 5, review Do sharks enjoy a nice beef cobbler of an evening? This chilling state of affairs could perhaps be mere days away, if you believe Channel 5"s Nature Shock: The Black Tip Shark Mystery. Over the past seven years, the Aliwal Shoal diving and fishing spot, off the east coast of South Africa, has been unprecedentedly infested with black tip sharks. Not only have these six-foot eating-machines been hoovering up all the fish, they seem to be communicating with each other in ways previously unheard of in sharks. Are they growing far smarter, and more sociable than it was previously believed possible? This was one of several questions raised but barely answered by this excitable documentary. To a soundtrack of stabbing strings and clattering drums, we followed the efforts of likeable lug Mark Addison to get to the bottom of the mystery. As he said, with a Wildean succinctness, "[it] isn't much fun to be outsmarted by a fish every day of your life," and who could disagree? Amid repeated shots of decapitated salmon and suchlike, this well-shot programme bustled melodramatically on to a single conclusion: that the sharks first showed up, and are refusing to leave, because of the vast amounts of sardines that diving expeditions (such as those run by Addison) throw into the water to attract marine life. So, human greed is the culprit, and Addison was the detective on his own trail - and that was pretty much that. Admittedly, it was interesting to learn that every one of these "gangster sharks" was female: where on earth were their fellas? A revelatory cut to 200 bull sharks cheering on the Springboks at the nearest sports bar was not forthcoming - but it's clearly only a matter of time. In Addison's blood-curdling words, "Maybe what's crazy now is not going to be crazy in the future."