During a train ride, an anxiety attack leads middle-aged illustrator John (Sir Alan Bates) into an identity crisis. As his marital problems merge and blur into his fantasy life with prostitutes and call girls, a long-dormant secret friend of his childhood surfaces in his delusions. Writer and Director Dennis Potter viewed John as "a victim of what he himself has created, a sexual fantasy that gets out of control. Fantasy should be one of the registered sexually transmitted diseases, which in John's case, it is."