British marathon swimmer Beth French wants to swim across seven of the world's most dangerous sea-channels - an extreme challenge called Oceans Seven - and do it in record time: within one year. Beth is a single mother, driven to set an example for her autistic son and by her battle with a life-long illness (ME) which resulted in her having to use a wheelchair for long periods of time as a teenager. During her extraordinary journey, Beth travels to far-flung corners of the world, where land meets sea. Once in the water, she confronts jellyfish, sharks, hypothermia, wild weather and mind-numbing fatigue, along with demons from her past. The rules for the swims are strict: no wetsuit is allowed – only regular swimwear, goggles and a cap – and no physical contact with the pilot boat or a person. Each swim can take up to 20 hours, often through the night, but, immersed by waves, Beth is in her element: “Being in water gives me freedom...It's where I belong." Her core team shadow her every stroke, shouting encouragement and writing progress reports. Beth — never less than single minded in pursuit of her aim — does not always take their advice, leading to friction and resignations. In-between swims at home, Beth struggles to balance fund raising, homeschooling her eight year old son and earning a living as a single parent. Her family, friends and local community rally to lend support. But ultimately this is Beth’s story and, in an extraordinary and emotional climax, Beth’s burning desire to conquer the open sea comes into heart-rending conflict with a mother’s dreams for her son.