(CNN)With Ben Ainslie, it's in the stare. Charming, polite, every bit the sailor-cum-businessman, the clothes are perfectly pressed with not a hair out of place. But it's the look in his brown eyes, the glare that offers a glimpse of the other side of sailing's Jekyll and Hyde. His friend and America's Cup rival skipper Iain Percy once described him as the "most competitive man on the planet." And on an industrial estate in a small, understated office -- quintessentially Ainslie -- in Portsmouth on England's south coast, Britain's greatest ever sailor is plotting how to win the America's Cup.
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British sailor Ben Ainslie is plotting a first British win in the America's Cup 163-year history
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Four-time Olympic champion was billed a modern-day Horatio Nelson for his 2013 Cup heroics
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Almost overnight, he has gone from a modest sailor to a CEO of a $130 million brand
While he used to be focused on winning @placeholder gold every four years, now Ainslie has myriad other tasks to think about.