She’s so comfortable – if not at home – in the water now, it’s hard to believe Valentine Thomas once almost drowned in it. Of course, that was a half a lifetime ago, when this spearfishing maven from London via Canada was vacationing seaside with her family in the south of France. Just 14, Thomas got caught in an undertow – not far from the shore, but far enough for a harrowing few seconds. “I was caught by the underwater currents. The current had suddenly changed and I remember sticking my head up and there was nobody in the water,”...