Amazingly grim, violent and intense, as one might expect from a first screenplay by Jimmy McGovern, this is also, alas, a tiresome and often unwatchable expanded short story about explosively jealous Christopher Eccleston, whose fury brings on a heart attack, his shallow wife (Kate Hardie) losing little time in starting a torrid affair with the arrogant, self-absorbed colleague (Rhys Ifans) who fancies her. After Eccleston has a successful heart transplant, this fusebox situation is made even more combustible by the addition of the donor's batty mother (Saskia Reeves) whom Eccleston is unwise enough to track down. All four are dislikeable, dangerous characters and you're glad to see the back of them. A sprinkling of unintentional laughs is poor compensation for the rest, and the heart ops are awesomely gruesome.