This is Simon Murie. He's standing on a grassy hummock on the shore of Buttermere in the Lake District, doing I forget what with a banana. A joke involving cold water and male shrinkage? Demonstrating front crawl with soft fruit?
He was one of two guides leading a swimming and camping trip we went on last weekend. Our other guide was Olly (below, in blue), who has been a beach lifeguard in Cornwall, a surf bum everywhere from Bali to Costa Rica, and is now a PE teacher in Cumbria.
The weather was shocking, but the scenery heartstopping.
Murie used to be a mining engineer, but decided nine years ago to turn his hobby – open water swimming – into a job. The result is Swimtrek, a company that runs outdoor swimming trips all over the world, from Turkey to Mexico (I went with them to Greece last year – weirdly warmer than northern England – and never laughed so much).
While the rest of us squeezed into our wetsuits and shrieked as we entered the 12 degree water, Murie stripped down to his shorts as if it were the Mediterranean in August. It's really not: at 12 degrees, the cold hits your face between your eyes, your lips turn numb and your hands, by the time you climb out, are incapable of movement until you've grafted them to a mug of tea.
Australian by birth, Murie has swum Hellespont in Turkey, the Channel, the River Volta in Ghana and the Gibraltar Straits. He goes on half a dozen Swimtrek trips a year, and spends the rest of his time scouting for new locations. He swam alongside me twice, shouting encouragement and giving me technique tips.
But what I admired most about him is his modesty. When introducing himself, he didn't tell us it was his company. He got up before breakfast to manufacture sandwiches with excellent humour. And he cracked jokes all weekend.
On our final swim – the length of Lake Buttermere (above) – a small girl shouted: "Look Mummy, they're going in again!" Yes, I couldn't believe we were either. But I'm still glowing.