A cop ostracised by his peers for being too honest investigates a drug dealer whose empire is growing at an exponential rate… hold on to your wide lapels, it’s Serpico meets Scarface!

But this absorbing, spiced-up history of Detective Richie Roberts’ pursuit and capture of real-life dope dealer Frank Lucas demands more respect than that.

To begin with, it’s a vast improvement on Russell Crowe’s last collaborations with Denzel Washington (1995’s dopey sci-fi Virtuosity) and Ridley Scott (2006 misfire A Good Year).

It also perfectly recreates an era rife with addiction, corruption and superfly fashion, and – thanks to the skill of Oscar-winning editor Pietro Scalia (JFK, Black Hawk Down) – makes two and a half hours of drug-dealing ‘bid-ness’ pass in no time at all.

Lucas was, first and foremost, a businessman. By smuggling heroin into the country via a military contact in Bangkok (how they did this was ingenious, despicable and no great secret - but it’s more fun not to know at the start) he was able to flood the market with purer, cheaper product.

A black man who beat the Italian mob at their own game, Frank was soon rubbing shoulders with boxing giant Joe Louis, marrying Miss Puerto Rico (Lymari Nadal), buying mansions for his dear old Ma (Ruby Dee) and making it a family business with ultimate responsibility going to his brother Huey (Ejiofor).

Washington is as charismatic as ever, yet Frank remains an enigma; his motives are never made entirely clear. What does occasionally surface is the ferocious temper lying behind that laid-back façade.

In the blue corner, Crowe’s Roberts is a rarity in the New Jersey PD: a cop who's not on the take. His decision to turn in a million dirty but eminently stealable dollars makes him a pariah, but it allows him to put together his own drug squad.

Money doesn’t interest Richie. His weakness is for women, which is why he is stuck in a bitter custody battle with his ex-wife (Carla Gugino)… and his first marriage is to the job anyway.

Among the multitude of peripheral players, Josh Brolin is a stand-out as Richie’s scuzzy rival in the NYPD. It would have been nice to see more of John Hawkes’ fellow narc and The Wire’s Idris Elba (his street-level big-shot gets a surprising comeuppance), though Cuba Gooding Jr gets just enough screen time not to ruin a rare decent role as a pimp-tastic dealer.

Scott and writer Steven Zaillian (another Oscar winner – for Schindler’s List) effectively shuffle the characters and spread the story smoothly over more than half a decade, using TV and radio broadcasts to provide a running commentary of world events.

It may not be subtle – intercutting Frank’s family enjoying Thanksgiving dinner with shots of his customers suffering all manner of intravenous misery is rather obvious – but then neither were the Seventies.

Frank took down 30 members of his family with him and Richie’s investigation led to a quarter of New York’s drug enforcement personnel being exposed as dodgy. But don’t think this is some sort of upright morality tale: Frank and Richie are now good friends.

American Gangster is the best product of its type since The Departed. Probably better.

Elliott Noble