When I approached these people I thought the girl with the camera was doing a really bad job of pretending to take the boat houses across the river while actually taking the people. When I got nearer I realised that the couple were in fact doing a very good job of looking like they were having a casual conversation while she took 'candid' photos of them. All of them were sufficiently preoccupied not to notice me taking quite a few shots!
Love the pic :)