Karl Foyle (Steven Mackintosh) and Paul Prentice (Rupert Graves) were boyhood friends back in the 1970s, but when they run into each other in present-day London, they learn that a lot has changed. For starters, Karl has become Kim and has no desire to go back to her past. As for Paul, he's just an aging punk with a dead-end job. The two rekindle their friendship and are surprised to find their relationship becoming much deeper than they expected.