In their fifth screen collaboration, Martin Scorsese and Leonardo DiCaprio produce the funniest work of their careers in this debauched and riotously indulgent black comedy depicting the rise and fall of Wall Street stockbroker Jordan Belfort.

On more than one occasion during Martin Scorsese’s sprawling three-hour film, Jordan Belfort (Leonardo DiCaprio) attempts to bring the audience up to speed with his nefarious insider dealings, before cutting himself off, dismissing the intricacies of financial double dealing to underscore the fact that what he and his employees were doing was illegal, but made them an obscene amount of money. This is the essence of what The Wolf of Wall Street is about. It’s not a film about the opaque, complex world of stock trading, but rather the silk-tongued, morally-bankrupt gatekeepers who did everything in their power to move their clients’ money into their own pocket, to paraphrase Matthew McConaughey’s dubious mentor Mike Hanna.

After earning his broker’s license just weeks before the stock market crash of 1987, Jordan Belfort turned to penny stock trading, where the prices were low but the commission ridiculously high. From a Long Island boiler room, Belfort proceeds to build his empire, but as his newly founded company, Stratton Oakmont Inc., expands in size, so does Belfort’s personal wealth. As well as fancy clothes, fast cars and opulent mansions, the money soon breeds drug addiction, sexual debauchery and increasingly dubious practices, eventually attracting the attention of the FBI.

In The Wolf of Wall Street, Scorsese returns to the directorial techniques of perhaps his greatest work, 1990’s Goodfellas. Based on Belfort’s own memoirs, and narrated by DiCaprio’s onscreen incarnation, we are whisked along in a blizzard of bank notes and cocaine as Belfort and his chief cohort Donnie Azoff (a gleefully ridiculous Jonah Hill) abuse themselves, each other, and pretty much anyone that crosses their paths on their way to becoming multimillionaires. They live a life of perpetual excess, permanently intoxicated by a crippling cocktail of alcohol, drugs and greed, going unchecked and unregulated in a bubble of hedonistic acceptance of their own creation. Women are treated almost as reprehensibly as their clients, and while the script does offer Margot Robbie a substantial role as Belfort’s second wife Naomi, she must fend for herself in a sea of misogyny and disrespect.

As with Goodfellas, the audience is taken along for the ride by the film’s central protagonist, and as with Henry Hill in that film, we only ever hear Jordan Belfort’s side of the story. Considering how much of these pivotal years he spent coked up to the eyeballs or debilitated by quaaludes, not to mention being a successful liar and shameless narcissist, the film must be ingested with a sizeable grain of salt. That said, to Scorsese and DiCaprio’s credit, they never portray Belfort as an enviable or heroic presence. He is always depicted as sleazy, conniving, obscene and depraved – but he also has a hell of a good time along the way.

The film embraces Belfort’s lifestyle, playing out its ceaseless merry-go-round of sex, drugs and depravity in minute detail to almost Caligulan levels. The film itself is an exercise in relentless excess, which for some has already proved too much. Scorsese would probably be the first to admit that he has belaboured the point here, but this is entirely deliberate. Belfort’s problem wasn’t having one coke-fueled pool party too many, or spending $2 million on his bachelor party, or even totalling his Ferrari while driving under the influence of illegal prescription drugs – but rather that this level of insanity had become his life. The reason The Wolf of Wall Street succeeds is because Scorsese is able to keep the momentum going on this ceaseless carnival of chaos, while Leonardo DiCaprio delivers a performance unlike anything we have ever seen from him.

DiCaprio is not an actor known for comedy, but he rightly won the Golden Globe last month for his chameleonic depiction of a social reprobate masquerading as a high-flying member of the business community. Charisma has never been a problem for the actor, and he oozes charm whenever necessary here, tipping into self-aggrandising narcissism whenever surrounded by his legions of adoring employees. But there is also an incredible physicality on display, particularly as Belfort’s drug use begins to consume him. With each film, and particularly his collaborations with Martin Scorsese, DiCaprio continues to grow, experiment and evolve into one of the most fascinating and versatile leading men currently working in American Cinema. The Wolf of Wall Street is just the latest example of a true Hollywood great continuing to challenge himself.

As Donnie Azoff, Jonah Hill again proves he is more than just another whiny comedian from the Judd Apatow stable. His character here is ludicrous, repugnant, yet often times hilarious, and as was true of Joe Pesci in Scorsese’s earlier films, The Wolf of Wall Street shifts up a gear whenever Hill is onscreen. Elsewhere, it’s great to see the likes of Jon Bernthal, Ethan Suplee, Shea Whigham and P.J. Byrne featuring in substantial supporting roles, alongside more established actors like Joanna Lumley, Jean Dujardin and Rob Reiner, while the long shadow of McConaughey’s brief cameo early on always threatens to creep back into frame.

For a long film, The Wolf of Wall Street moves at a cracking pace, so even when Belfort’s antics become repetitive and monotonous – which they do – the film remains entertaining throughout. While the real Jordan Belfort was apparently closely involved in the production, Scorsese still manages, if barely, to hold his subject at arm’s length and assess him objectively. There is no doubt he was an incredibly charismatic boss, who successfully commanded an army of like-minded brokers to become very successful at what they did, but the film still shows us what a reprehensible idiot the man could be. And that contradiction is what epitomises Jordan Belfort best of all. People did believe him, love him and worship him, despite the fact he was a liar, a cheat, an addict and a crook. And despite their better judgement. That The Wolf of Wall Street makes us laugh at his absurd behaviour, be appalled by his business practices, yet still feel a tinge of jealousy as he languishes on his yacht, a beautiful woman on each arm, proves that Scorsese and DiCaprio have both done their jobs – and done so with more honesty and integrity than Jordan Belfort ever had.