In a life crisis, British adventurer Roger Deakin makes a wild decision: he will swim through all the waters of Great Britain, equipped with a thin wetsuit and driven by the desire to re-measure his homeland - from a frog's perspective, with his eyes always just a few centimeters above the water's surface. On his year-long journey, he swims through icy mountain lakes as fearlessly as he does through dirty irrigation ditches and wild river currents, encountering salmon in Somerset, eels in the marshes of East England, and swimmers in the Hampstead Ponds. What begins as a lived dream of swimming soon takes on dreamlike qualities in his fascinating descriptions. Thus, the logbook of a swimmer becomes a self-portrait of an extraordinary man, which can also be read as a political manifesto against the privatization of waters and nature.