The film paints a bleak picture of the kind of housing-estate London which one hopes doesn't exist in too many places in reality. Caine is hugely impressive in an understated way as the ill pensioner living in a dingy apartment in a miserable high-rise estate dominated by drugs, guns and fear. The death of his ill wife and the murder of his friend Len in an underpass (the underpass that no-one dare use) tip the balance and Caine - the ex-Marine (well, what do you expect, an ex-ballet dancer?) - cracks, stabbing a knife wielding druggie who tries to rob him. Detective Inspector Frampton (Emily Mortimer) does her best to pull in Len’s killers, but the police are powerless, so it is Caine who seeks reluctant revenge.
Inevitably it all builds to a violent climax, with fire-bombing rioters providing the back-cloth (deliberate comparison with Northern Ireland here) as Caine and Mortimer try and take down the chief scumbag and his Irish uncle (why Irish?). This is then, in short, an entertaining film, with Caine ably combining two of his hallmark personas - the charming old codger and the brutal killer. He was a pleasure to watch.