Joe is released from prison for a crime he says he didn't commit. With four months of his sentence remaining he receives a discharge grant of £46 and is driven to a hostel, where a security worker fits an electronic tag to his ankle.It's a demeaning experience until he discovers that the tag is waterproof. For Joe - a former champion swimmer - the future suddenly seems a little brighter.When he returns to his local swimming pool, where he was once a popular member, he soon attracts the attention of single mum Lisa. But his budding romance is jeopardised when he neglects to tell his new girlfriend about the prison tag - and his 7pm curfew…