One hot June day, three friends decide there is nothing they would like to do more than to get away from London. A boating holiday with lots of fresh air and exercise would be just the very thing, or so their doctors tell them. So, after debating the merits of hotel or camp beds and what to pack, they set off on their voyage - a trip up the Thames from Henley to Oxford - but very quickly find themselves ill-equipped for the trials of riverbank life.