Something as insignificant as a cigarette butt can be used by forensic researchers to find and convict criminals. This week's Modern Marvels (11pm History Channel) investigates.
GENE HACKMAN (right) is one of the world's most solid actors; he has appeared in many bad films without ever giving a bad performance himself. He is perfectly cast in The French Connection (10pm Sky Cinema) as Popeye Doyle, a great cinema creation. In this Oscar-winning film, the tough-guy cop, who is not afraid to break the law when it suits him, takes on the drugs trade. William Friedkin's thriller - which went by the memorable catchline of "Doyle is bad news... but a good cop!" - was drawn from the real-life deeds of a maverick police officer called Eddie Egan. It is rightly celebrated for its portrayal of the seedier side of New York.