PERFECT SEPTEMBER DUSK. Tide low, water still. We scrunch wet sand beneath our shoes, facing the rocky cliff opposite. A hooded human in a light-coloured coat enters left, across the water. The figure slowly walks, stretches, crawls, lies, curls – crossing our field of view, always just on top of the water. A black head at the waterline some metres in front is the only clue. The scene is accompanied by a flautist standing in the shallows, and later by readings from historical diaries that echo off the cliffs. We are all captivated, savouring the surreality along with the brackish whiff of the river and the thickening darkness. But we also wonder: how are they doing that?

Over dinner, some of the engineering and performative intricacies emerge. The raft was supported by milk crates with plastic bottles half full of water, calibrated to provide exactly the right amount of flotation. The tide and sunset times could be predicted, in order to bring the audience to the stage at the precise time. This art had a lot of science behind it. The stillness after a windy afternoon was perfect, but just lucky.