John Lee, a young Chinese man who frequents a public toilet in London's Bethnal Green, ignores the unwritten rule that gay men shouldn't fall in love with straight men. After a chance sexual encounter with one William Hope in the lavatory, John finds himself hopelessly smitten with Will, an anxious, white "straight" guy who insists that he isn't one of that kind. After all, he claims indignantly, "A mouth is a mouth."
It appears that the two men are no strangers to cottaging, and eventually establish a kind of pseudo-relationship, where John willingly gives and Will greedily takes. When Will decides to abruptly end his casual escapades, the vulnerable, self-loathing John fires six shots into his part-time lover, killing him in what is later referenced as a "crime of passion." The two men are found at the very origin of their union, "one dead, and the other living with a gun by his side."
Following a whirlwind of media sensation and public reproach, it is then up to slick-tongued psychologist Dr. Worthing to determine whether or not John was sane at the time of the murder. Using stock Rorschach ink blot tests to determine John's psychological health while unwittingly exposing his own prejudice and homophobia on air to Channel Four, Worthing must pull a few tricks out of his bag to convince John to trust him and reveal his side of the story.
